Whether you’re designing integrated circuits, equipment, or systems, you absolutely must provide protection from electrostatic discharge (ESD). ESD is a common problem in most environments.  Product failures from ESD lead to enormous reliability issues that can increase costs, drive customers away, and give your products a poor reputation.

Designing in ESD protection may be a boring process, but it’s an essential part of creating new circuits or equipment today. It’s one of those things that you don’t have to like, but need to do if you’re going to avoid having your products labeled as a catastrophe. The good news is that multiple solutions are available to make adding ESD protection fast and easy.

Explaining ESD

ESD is that sudden transfer of static electric charges from one object to another, where each object has a different electrostatic potential. Almost all objects will pick up a charge of electrons when it touches some other object. Walking on a carpet will cause you to pick up a charge of many volts that will be felt as a momentary shock when touching some nearby metal object. Handling anything plastic, such as a Styrofoam cup or plastic bag, will cause a charge build up.

This difference of charges represents hundreds or even thousands of volts. When the two objects with different charges are brought together and touch, the resulting transfer of electrons produces a high current flow. The results are thermal levels that can melt material or the breakdown of dielectrics in an IC. The outcome is usually a catastrophic failure of semiconductor devices.

1. Shown is a typical ESD transient pulse and how it can be suppressed with a TVS diode.

Download this article in PDF format.

Whether you’re designing integrated circuits, equipment, or systems, you absolutely must provide protection from electrostatic discharge (ESD). ESD is a common problem in most environments.  Product failures from ESD lead to enormous reliability issues that can increase costs, drive customers away, and give your products a poor reputation.

Designing in ESD protection may be a boring process, but it’s an essential part of creating new circuits or equipment today. It’s one of those things that you don’t have to like, but need to do if you’re going to avoid having your products labeled as a catastrophe. The good news is that multiple solutions are available to make adding ESD protection fast and easy.

 Sponsored Resources: 

• Critical selection parameters and standards ratings for ESD protection devices
• System-level ESD protection
• ESD224 HDMI 2.0 Compliance and Protection

Explaining ESD

ESD is that sudden transfer of static electric charges from one object to another, where each object has a different electrostatic potential. Almost all objects will pick up a charge of electrons when it touches some other object. Walking on a carpet will cause you to pick up a charge of many volts that will be felt as a momentary shock when touching some nearby metal object. Handling anything plastic, such as a Styrofoam cup or plastic bag, will cause a charge build up.

This difference of charges represents hundreds or even thousands of volts. When the two objects with different charges are brought together and touch, the resulting transfer of electrons produces a high current flow. The results are thermal levels that can melt material or the breakdown of dielectrics in an IC. The outcome is usually a catastrophic failure of semiconductor devices.

1. Shown is a typical ESD transient pulse and how it can be suppressed with a TVS diode.

Figure 1 shows what a common ESD pulse looks like (red curve). The transient duration is short, typically several nanoseconds, but mostly less than 100 ns. Such destructive pulses can be minimized by connecting a transient-voltage-suppressor (TVS) diode from the signal line to ground. The TVS diode is like a Zener that conducts and clamps the voltage at some safe lower level. The result is the blue curve.

The most vulnerable devices are ICs made of MOSFETs or discrete MOSFETs. These transistors have a tiny gate with a super-thin dielectric that’s easily broken down with ESD. Today, most CMOS ICs and discrete MOSFETs incorporate some minimal internal ESD protection. While the internal protection eliminates some problems, it may be inadequate in other applications. Therefore, many products also incorporate external ESD protection.

As MOSFET sizes decreased over the past years to increase switching speed and reduce chip space, these devices have become even more susceptible to ESD. Internal chip protection routinely needs external assistance to curb the eventual exposure to ESD during product assembly, testing, shipping, or usage.

Any product with a high-speed interface, such as HDMI, Ethernet, or USB, is especially susceptible to ESD if it has an external connector to the outside world where humans can come into contact. Audio and RF antenna connections are also vulnerable. It only takes one ESD strike to permanently damage a product, which makes ESD protection a critical part of a system design.

The most common way to protect sensitive inputs and outputs of an IC or other circuit is to connect a TVS diode between the line carrying the signal and ground. If an ESD pulse occurs, the diode will shunt the resulting current to ground protecting the circuitry. External protection diodes are available to ensure that no damage occurs. To specify an ESD TVS diode, you need to understand the critical selection parameters and standards ratings for ESD protection devices.

ESD Diode Selection

ESD protection diodes are similar to Zener diodes in that they’re designed to conduct at a certain voltage level. Common schematic symbols for these TVS diodes are shown in Figure 2. The back-to-back connected Zeners protect against both positive and negative transients.

2. Common ESD protection diode schematic symbols include Zener diode TVS (a), bidirectional TVS (b), and functional configuration of a bidirectional TVS (c).

What follows are the most common ESD specification parameters:

• Working voltage: This is the main voltage rating that states the level where the devices begins to clamp and limit the voltage. It must be higher than the logic-signal voltage levels to avoid compromising the signal integrity. The voltage level may be positive, negative, or both.
• IEC rating: The International Electrotechnical Commission (IEC) has the standard 61000-4-2, which states the amount of voltage that the device can withstand. Two measures are given—the contact voltage and the air-gap voltage. Contact voltage is the transient discharged directly into the protected device. The air gap voltage is the transient level discharged into the device via an air gap. Four levels are given, with the highest level 4 specifying 8-kV contact voltage and 15-kV air-gap voltage.
• Capacitance: When a protection diode is connected from the signal line to ground, it adds shunt capacitance that will extend signal rise and fall times and seriously limit the data rate. This capacitance must be small (< 1 pF) to maintain good signal integrity. Eye-diagram tests are routinely used to see if the signals meet the requirements of the standards.
• Clamping voltage: This is the voltage level where the diode conduction kicks in and limits the level to the IC. The clamping voltage is generally extrapolated from a transmission-line-pulse (TLP) curve that shows the relationship between the clamping voltage and diode current. The TLP curve is usually given in the datasheet.
• Channels: Interfaces have multiple signal lines that are present at connectors. Each line is a channel and all of them need to be protected. Multichannel ESD protection devices are available to simplify and minimize PCB layout.

To select an ESD component, consider Texas Instruments’ line of ESD protection devices that can handle almost all common applications.

ESD Design Process

Based on the design factors given earlier, here is a step-by-step procedure for selecting an ESD diode.

1. Determine the number of channels (IC pins or interface lines) to be protected.

2. Determine the logic voltage range of each channel on the device or interface. Most are positive voltages of 5 V or less. The protection diode’s working voltage should be a little bit higher than the maximum expected logic voltage.

3. Determine if you need a unidirectional or bidirectional protection diode. A unidirectional diode is typically all that’s required unless bipolar logic voltages are involved.

4. Determine the maximum possible capacitance that the device or interface line can withstand. It helps if an overall capacitance budget is known. Otherwise keep the capacitance of the diode as low as possible.

5. Determine the clamping voltage. It should be as low as possible, but not interfere with normal operations. Estimate the clamp level from the TLP curve in the datasheet.

6. A good rule of thumb is to also specify a diode that meets the IEC 61000-4-2 level 4 specifications of 8-kV contact voltage and 15-kV air-gap voltage.

Texas Instruments offers several selection and design tools to help you choose products appropriate and most of the popular interfaces.

Design Example

Consider the goal to protect an HDMI 2.0 interface. The High Definition Multimedia Interface is widely used in consumer video and audio connectivity. The cables and connectors are routinely handled by humans and subject to considerable instances of ESD. ESD diodes eliminate the problem.

3. In this example of using a four-channel ESD device on an HDMI 2.0 interface, the data lines are protected with two ESD224 devices while the auxiliary lines are protected with TPDxE05U06 devices.

Figure 3 shows the typical basic HDMI data connections. The HDMI interface consists of four differential pair data lines (3 data, 1 clock) and six other control and data lines. All should be protected. Typical logic levels are 3.3 V. One approach is to use the TI TPD1E05U06 single TVS device; one for each data line. Alternatively, you can use the TPD4E05U06 that contains four TVS devices. Two of these ICs handle the four differential data lines.

Another choice is TI’s ESD224, a bidirectional TVS ESD protection diode array for high-speed applications. The ESD224 employs four on-chip, differentially matched series elements to enhance downstream ESD clamping performance while maintaining the signal compliance for HDMI. The goal of the ESD224 is to provide a low clamping voltage device while still being able to pass HDMI 2.0’s 6-Gb/s signals. For more detail on the ESD224, see the information at the link below.

More information on ESD and its mitigation is available in Texas Instruments’ series of short (<4 minute), easy-to-digest videos that explain all of essentials required to protect against ESD.

 Sponsored Resources: 

• Critical selection parameters and standards ratings for ESD protection devices
• System-level ESD protection
• ESD224 HDMI 2.0 Compliance and Protection

References

Vinson, J., Bernier, J., Croft, G., and Liou, J., ESD Design and Analysis Handbook, Kluwer Academic Publishers, 2003.

Wang, A., On-Chip ESD Protection of Integrated Circuits, Kluwer Academic Publishers, 2002.

Adesto Technologies announced that it would acquire S3 Semiconductors for $35 million in cash and credit, moving beyond its core business of memory chips. The Dublin, Ireland-based company makes mixed-signal, analog and radio frequency chips and it will become a business unit inside Adesto.

Narbeh Derhacobian, chief executive of the Santa Clara, California-based Adesto, said on Thursday that the acquisition was “a meaningful step in becoming a supplier of a broad range of innovative semiconductor products and solutions for the IoT markets.” He added that S3 Semiconductor's products would expand Adesto’s customer base and serviceable market.

Adesto added that the acquisition would help it expand in markets like communications and the industrial Internet of Things. With S3 Semiconductor’s products, the company will be able to supply a larger percentage of parts inside embedded devices, ranging from smart home appliances to factory sensors. The deal also gives it more embedded and mixed-signal engineering expertise.

Applications that require the control of a motor typically involve some type of current-sensing circuitry. Being able to sense the current through the motor allows adjustments, such as speed, to the motor’s current state if needed.

For example, in drones, each of the motors that control the propellers typically use a low-side current-sensing circuit to steer, stabilize and lift the drone through the air. In power tools like drills and reciprocating saws, low-side current sensing controls the speed of the tool based on how hard users pull the trigger. These products typically require a cost-sensitive design because they are sold in the consumer market space. In this blog post, I’ll discuss how to design a low-side current-sensing circuit for cost-sensitive applications.

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In my previous blog post, I discussed how low-side current sensing helps control a motor and then provided three steps to design a low-side current-sensing circuit for cost-sensitive applications. In this post, I’ll discuss how you – with the proper printed circuit board (PCB) layout techniques – can design an accurate, low-cost, low-side current-sensing circuit with a single tiny operational amplifier (op amp).

Figure 1 displays the schematic of the low-side current-sensing circuit in my previous blog, shown here using the TLV9061 tiny op amp.

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It’ll come as no surprise to any savvy buyer, and certainly not to any design engineer, that each new generation of electronic products packs more performance into a smaller package than the product it replaced (Fig. 1). No matter whether it’s a remote industrial sensor node or the next smart wearable device, space is becoming an increasingly scarce resource.

1. Better not sneeze: Aimed at IoT and personal electronics applications, the TLV9061 consumes only 0.64mm² and is the world’s smallest op amp. (Source: Texas Instruments)

Something’s gotta give. In this case, many things. Fitting the increased capability into a smaller volume requires the designer to make improvements in multiple areas. The three biggest keys to succeeding, however, are to reduce the overall power consumption to allow the use of a smaller battery; integrate multiple functions into a single package to cut down on the number of devices; and choose individual components in the smallest available packages.

Manufacturers of both active and passive devices are keenly aware of the push toward smaller sizes. Just look at resistors, for example. Back in the old days before surface-mount technology (SMT), the standard small-signal resistor was a 1/8-W axial through-hole device measuring about 1.8 mm in diameter and 3.0 mm long, plus extra for the leads. The equivalent now is the 0201 surface-mount resistor. Yes, it only handles 50 mW, but it measures 0.3 × 0.6 mm, a reduction in area of 96%.

Integrated circuits are following a similar path. In some cases, manufacturers can reduce the overall size of their products by integrating more functions into a single part. Even single-function devices, though, such as op amps and LDO regulators, are undergoing some serious shrinkage—from leaded dual-inline packages to SOICs to SOT, and below. Traditional packages are much larger than the die they contain, as they must also house the lead frame, the bond wires, etc.

Download this article in PDF format.

It’ll come as no surprise to any savvy buyer, and certainly not to any design engineer, that each new generation of electronic products packs more performance into a smaller package than the product it replaced (Fig. 1). No matter whether it’s a remote industrial sensor node or the next smart wearable device, space is becoming an increasingly scarce resource.

1. Better not sneeze: Aimed at IoT and personal electronics applications, the TLV9061 consumes only 0.64mm² and is the world’s smallest op amp. (Source: Texas Instruments)

 Sponsored Resources: 

• Small size amplifiers for difficult system designs
• Small size data converters break through your toughest design barriers
• Big reductions thanks to tiny packages 

Something’s gotta give. In this case, many things. Fitting the increased capability into a smaller volume requires the designer to make improvements in multiple areas. The three biggest keys to succeeding, however, are to reduce the overall power consumption to allow the use of a smaller battery; integrate multiple functions into a single package to cut down on the number of devices; and choose individual components in the smallest available packages.

Manufacturers of both active and passive devices are keenly aware of the push toward smaller sizes. Just look at resistors, for example. Back in the old days before surface-mount technology (SMT), the standard small-signal resistor was a 1/8-W axial through-hole device measuring about 1.8 mm in diameter and 3.0 mm long, plus extra for the leads. The equivalent now is the 0201 surface-mount resistor. Yes, it only handles 50 mW, but it measures 0.3 × 0.6 mm, a reduction in area of 96%.

Integrated circuits are following a similar path. In some cases, manufacturers can reduce the overall size of their products by integrating more functions into a single part. Even single-function devices, though, such as op amps and LDO regulators, are undergoing some serious shrinkage—from leaded dual-inline packages to SOICs to SOT, and below. Traditional packages are much larger than the die they contain, as they must also house the lead frame, the bond wires, etc.

In a chip-scale package, the size of the package approaches the size of the integrated circuit itself. This package requires specialized manufacturing techniques, but brings benefits in addition to smaller size. For instance, the shorter interconnections reduce parasitics, giving improved performance.

Figure 2 shows a selection of packages for devices from 4 to 81 pins, ranging from the plastic dual inline package (PDIP), first introduced in 1964, to current-generation chip-scale offerings. Of course, this isn’t the complete list. It doesn’t include specialized packages, high-power packages, or packages with higher pin counts. The plastic ball-grid-array (PBGA) package can have up to 976 connections!

2. Here are some of the package options available for a single-function device. (Source: TI PDF: Packaging Solutions)

A Real-World Example: Data Acquisition

At the most basic level, a data-acquisition system takes in analog information from the real world, converts it to digital form, and uses the data to produce a desired result. Variations are found everywhere: in the factory, strapped to your wrist, at home, and in the doctor’s office, for example.

A data-acquisition signal chain has several distinct blocks:

• An analog front end (AFE) captures data from one or more sensors and converts it to digital form. This AFE typically includes pure analog components like op amps, and mixed-signal components such as analog-to-digital converters (ADCs).
• A microcontroller receives the data, processes it, and acts on the information.
• A mixed-signal output device such as a digital-to-analog converter (DAC) converts the microcontroller digital output back into analog form, perhaps to power a loudspeaker or actuator
• A power circuit takes input power and provides regulated supplies for all the devices

Although each one of these blocks has benefitted from the move to tiny packages, let’s examine the op-amp and data-converter portion of the signal chain and see how new package options allow designers to dramatically reduce size while simultaneously increasing performance. 

Tiny Op Amps Fill Many Roles

As fundamental building blocks in the signal chain, op amps must keep pace with emerging electronic design trends, including the move to successively smaller packages. 

How do manufacturers add smaller package options to a part? For existing parts, they simply repackage the device without changing the underlying circuit. The venerable TL071 low-noise JFET op amp, for example, now comes in five different packages. While adding packages, older devices will typically still offer the original package options until the device itself is discontinued—nobody likes a manufacturer who forces them to re-layout their design. But newer devices offer both smaller packages and improved performance.

Portable audio requires tiny devices to produce high-quality sound for smartphones, Blu-Ray players, and headsets. Traditionally, designers have used precision audio op amps in DIP packages for audiophile products. The OPA2134 from the legacy Burr-Brown product line is one such device. It has low distortion, low noise, and has been a professional audio staple over the years.

But its PDIP and SOIC packages are an issue for portable applications with severe space constraints. Designers can now choose the OPA1652(Fig. 3), which features upgraded performance and a smaller package compared to the OPA2134.

3. In addition to a dramatic size reduction, the OPA1652 audio op amp provides superior THD+N performance over the classic OPA2134. (Source: TI Archives: “Achieve big board-size reductions with tiny, precision op amps”)

Performance-wise, the OPS1652 has lower noise (4.5 nV/√Hz at 1 kHz) and lower THD + N (0.00005%) than the OPA2134 (8 nV/√Hz and 0.00008%, respectively).

The OPA1652 is available in several packages, including the WSON no-lead package that features a thin profile for handheld applications. The OPA1652’s version (DRG package code) has an exposed thermal pad and measures 3.0 × 3.0 mm—much smaller than the OPA214’s standard PDIP package (6.35 × 9.81 mm).

For general-purpose use, the OPA171 is worth considering. It’s is one of the first micropower 36-V op amps offered in both a single SOT553 (1.6 × 1.6 mm) package and a dual, very-thin shrink small outline package (VSSOP) (2.0 × 3.1 mm).  

In addition to changing to tiny packages, new op amps are adding specialized features for new applications. Many battery-powered products spend much of their time in sleep mode and wake up periodically to perform scheduled operations, process an incoming message, or respond to an interrupt. A fitness band, for example, only wakes up to measure biometric data; when the user presses a button; or when pinged by a paired smartphone.

Conserving battery life is a top priority in these applications. In sleep mode, it’s important to shut off as many devices as possible. While awake, the device must only power the blocks that are needed for the operation being performed.

These requirements have led to low-power op amps with a shutdown feature. The OPA2316S, for example, is a low-power CMOS op amp with a bandwidth of 10 MHz. The part operates down to 1.8 V and offers rail-to-rail input and output (RRIO) operation, making it suitable for low-voltage battery-powered devices. In shutdown mode, the OPA2316A consumes 0.01 µA typical. For the smallest size,  it comes in a quad flat-pack no-lead (X2QFN) package measuring 1.5 × 2 × 0.4 mm.

Data Converters: Linking the Analog and Digital Worlds

The ADC and the DAC are two important blocks in the signal chain. Analog-to-digital conversion occurs on the input side; tiny packages are appearing in this category as well.

Numerous data converters are available in tiny packages. Here are a couple of examples.

The ADS7040 is an ultra-low-power, 8-bit ADC that targets low-power data-acquisition, portable medical, and wearable applications, among others (Fig. 4). This device also comes in the X2QFN package. Although it uses the successive-approximation register (SAR) architecture to achieve 1 Msample/s, the ADS7040 consumes only 171 µW when powered by a 1.8-V battery cell. 

4. The ADS7040 shrinks a 1-Msample/s SAR ADC down to 2.25 mm². (Source: TI PDF: ADS7040)

On the output side of the house, the DACx0504 is a pin-compatible family of low-power, four-channel DACs with 16- and 14-bit resolution and buffered voltage outputs. The DACx0504 includes a 2.5-V, 5- ppm/°C internal reference, eliminating the need for an external precision reference in most applications.

The device operates from a single 2.7- to 5.5-V supply, is monotonic, and provides ±1 LSB integral nonlinearity (INL) performance. The DACx0504 communicates via a 4-wire SPI-compatible serial interface at up to 50-MHz clock rate. Best of all, the DACx0504 is available in a 16-pin WQFN package (package code RTE) that measures 3.0 × 3.0 mm.

Layout Guidelines for Small Packages

Using tiny packages allows you to shrink the size of the design, but the small package dimensions leave very little room for error. It’s important to follow manufacturer’s recommendations when laying out the printed-circuit board (PCB) and later during manufacturing. Texas Instruments offers application notes that provide guidance for many tiny packages.

Three primary factors can make the difference with regard to package size and pitch: PCB manufacturing, solder application, and component placement.

Here are some general rules, using the Extra Small Outline No-Lead (X2SON) package as an example. This package comes in 5-pin (code DPW) and 6-pin (DTB) versions that measure 0.8 × 0.8 mm and 0.8 × 1.0 mm, respectively. These packages are used by both logic and analog devices including the TLV9061 shown in Fig. 1, a 10-MHz CMOS op amp that finds homes in many consumer and industrial applications.

PCB Manufacturing

The PCB footprint for the X2SON packages requires a spacing of 0.208 mm (8.2 mils), which is well within the limits of most established PCB manufacturers. The primary manufacturing concern comes from the method used to connect to the center pin(s).

There are two layout options for the center pin: place a trace on the same layer as the other pins; or use a via to connect to a trace on another layer. Figure 5 shows recommended clearances in each case. Consult the guidelines in the application note for more information.

5. Shown are recommended layout clearances for the X2SON center pin: trace on same layer (left) and trace on separate layer (right) (Source: TI PDF: “Designing and Manufacturing with TI’s X2SON Packages”)

Solder-Paste Application

Solder-paste application is an area of concern when the pads are very small. For instance, the correct amount of solder needs to be placed on the pads. There are several variables, including stencil thickness, solder type, and aperture size and shape. However, the X2SON packages maintain a 0.4 mm (15.7 mils) pitch, which allows for more error in the assembly process while maintaining a high yield. When following recommended guidelines, industry-standard Type III solder paste can also be used.

Component Placement

Using a one-third pad placement error as a guideline, the X2SON-5 package requires a minimum placement accuracy of ±83 µm (3.28 mils) to seat the part properly; the X2SON-6 requires an accuracy of ±72 µm (2.94 mils). The one-third pad error tolerance enables all pins to make good contact with the solder paste and be in reasonable alignment with their pads. During the solder process, the surface tension of the melted solder will align the part. Pick-and-place machines can typically place a component with an accuracy of ±30 µm, well within the requirements for the X2SON.

Resources and Information

Application guidelines are available for many of the newer tiny packages. AN-1112, for example, covers the die-size ball-grid-array (DSBGA) wafer-scale package. The complete list can be found here, including information on older through-hole and power packages.

For analog and logic devices, you can browse through the Analog and Logic Packaging guide. It lists all of the available packages by pin count, with photographs of each one. Find out more about TI’s broad packaging portfolio at this link.

 Sponsored Resources: 

• Small size amplifiers for difficult system designs
• Small size data converters break through your toughest design barriers
• Big reductions thanks to tiny packages 

Steerable radar systems use mechanical means to adjust a single antenna element. Phased-array radar utilizes multiple fixed antennas to perform a similar function. The challenge with phased beamforming is that the electronics must be replicated for each antenna within an array.

Analog Devices’ GaN-based ADAR1000 X/Ku band beamformer chip can handle four antennas at once (Fig. 1). The chip supports a frequency range from 8 to 16 GHz. Maximum operating gain is 20 dB for the transmit side and 9 dB for the receive side. It has 360-deg. phase control with a 2.8-deg. phase-control resolution and 31-dB gain control. A single pin handles the transmit/receive toggle. It fits in a 7- × 7-mm LGA package.

1. Analog Devices’ ADAR1000 X/Ku band beamformer can handle four antennas.

A typical 16-element antenna array would require four ADAR1000 chips (Fig. 2). The ICs, like the beamformer chips, are normally found on the back of the PCB, helping to reduce the size of the system. The result is a compact, low-profile phased-array radar system.

Phased-array systems have a number of benefits in addition to eliminating the mechanical aspects of the alternative. Beamsteering is normally faster and has the ability to create nulls that eliminate or mitigate jamming and interference. The system can fail gracefully if a single element is lost.

2. This 16-element antenna (left) would use four ADAR1000s on the back (right).

One of the challenges for tight integration is cooling. The thermal considerations become more important as more chips are placed closer together. Thus, low-power chips like the ADAR1000 help to reduce these problems. The compact chip size is important—the placement and density of the antenna elements can be limited if the support chips take up too much space.

The number of elements within a system can easily be scaled up since everything is operating in parallel. Larger arrays are simply collections of more antenna elements along with the support chips that include the beamformer, mixers, and transceivers.

Analog Devices has reference designs that provide a complete radar solution. Most of the additional chips, such as the digital-to-analog and analog-to-digital converters (DACs and ADCs) are also provided by the company.

Electronics has been a hobby for as long as electronics has existed. It started with radio in the early 1900s, and has continued to this day. Audio was a big focus in the 50s and 60s, but hobbyists turned to micros, computer kits, and PCs in the 70s and 80s. That interest in micros continues to this day.

There have always been publications covering the hobby aspects of electronics, and today multiple websites serve this community. It’s hard to pin point the number of participants, but in general, the hobbyist population appears to be growing. Many working engineers are also hobbyists. Are you one?

I definitely “are” one, as they say. I started out in my early teens with radios, taking them apart and learning about shortwave listening and ham radio with my Dad’s Hallicrafters S38B radio. I got my ham license soon after, and have been involved with that hobby up to the present. I’m a ham extra class, W5LEF. In the 1970s, I worked for Heathkit and was involved in developing the Heath computer kits. I still play around with electronics and have my own workbench with multiple radios, scope, power supplies, breadboards, etc., to try out circuits and equipment. It’s still fun for me. I suppose that makes me somewhat of a geek. Whatever.

Maker Faire Austin

Recently, I attended the Maker Faire here in Austin to see what that was all about. This is one of many events associated with Maker Media, the publisher of Make magazine. Maker is the latest term for hobbyists and any do-it-yourselfer (DIYer). That includes not only electronics, but a wide range of hobbies and crafts. Some of those on display at the show were woodworking, metal working (such as welding), 3D printing, rocketry, robots, quilting, and sewing.

The Maker Faire brings together all those makers who want to show off their projects and to see what others are doing. It’s a mixed bag of displays and demos. I was particularly awed by the drones and the Legos art. And cardboard. Yes, cardboard. Impressive what you can build with cardboard boxes. It’s truly amazing what people are building and experimenting with. A major portion of makers are kids, but I saw more than a few gray-hairs, too.

Electronics seems to be involved in many maker projects. I did see some miniature Battle Bots, not full-sized ones, though. And there were multiple robots roaming around and doing tricks. Some other electronic-related exhibits included an 8-bit all-relay computer, antique electrical and electronic measuring devices, plenty of creative LED displays, and a ham radio exhibit.

The emphasis today in electronics making is embedded controllers. The Arduino was ubiquitous at the show, but the Raspberry Pi isn’t far behind. And there were several Internet of Things (IoT) demonstration projects. It’s clearly a digital world.

If you have not been to a Maker Faire, take a look next time one shows up near you. The diversity and ambition of it all is impressive. Hopefully some of these makers will become engineers.

As for ham radio, it’s booming these days. According to the American Radio Relay League (ARRL), a supportive amateur radio organization, during 2017, 30,000 new ham licenses were issued. That brings the U.S. ham population to just over 748,000. It just so happens that hams are also major makers. Antennas are a continuous focus, and low-power (QRP) transmitters are a favorite exploration. Some of the new narrow bandwidth digital modes (PSK31, JT65, JT9, and others) of operation are increasingly popular, as is experimentation with the ham satellites, moonbounce, and some of the gigahertz bands.

Who are the Hobbyists?

A recent study of electronic hobbyists revealed some interesting facts. It was sponsored by Jameco Electronics, a popular source of electronic parts for hobbyists. I’ve been buying chips and other stuff from them for years. They did a survey of 1,700 participants who are probably representative of the average U.S. electronic hobbyist today. Here’s a summary of what I saw in the survey report:

• Average age is 56. That surprised me. Only 7% age less than 30.
• 66% have a college degree (34% EE), 30% with a graduate degree.
• 35% are self taught.
• Most hobby time is spent on project design (44%) and building (24.4%), and on fixing stuff (22.1%).
• Microcontroller projects and LEDs seem to dominate the interests.
• Most electronic hobbyists hate surface-mount devices (SMD). No surprise here.

For more details, contact Jameco for the full report by clicking here.

Electronic hobbyists are alive and well. You can learn more from some of their publications, such as Circuit Cellar, Make, and Nuts & Volts magazines. And ham magazines like QST (ARRL) and CQ. Moreover, dozens of websites are devoted to hobbyists.

Electronics is fun because it is a learn-by-doing hobby. You also learn what not to do. Haven’t you ever zapped an expensive transistor or IC by unintentional static electricity? Or wired a diode or electrolytic capacitor in backwards? Or been shocked? Or cussed while trying to solder an SMD? If not, time to join the fun.

Power semiconductors are a key component in the worldwide shift toward electric vehicles and renewable energy sources like solar and wind. And so Infineon Technologies, grappling with voracious demand, is aiming to boost its supply of the chips with the construction of a new $1.9 billion factory in Europe.

Infineon, the world’s largest maker of power semiconductors with 18.5 percent market share, plans to start building by the first half of next year, with the investment to be spent over six years. The factory located in the Austrian city of Villach is expected to enter production of 300-millimeter wafers by 2021, creating about 400 jobs.

“Growth is underpinned by global megatrends such as climate change, demographic change and increasing digitization,” said Infineon's chief executive officer Reinhard Ploss. “Electric vehicles, connected and battery-powered devices, data centers or power generation from renewable sources require efficient and reliable power semiconductors.”

“Global demand for power semiconductors is soaring,” Ploss said in a statement. “We recognized that trend early on” and the Munich, Germany-based company’s new production plant “will help us cater for the growing demand that our customers anticipate, and continue on our path to success in the coming decade,” he said.

Over the last year, the supply of power semiconductors has been lagging demand. Discrete semiconductors are on allocation for an average of almost four months, according to Electronic Components Industry Association estimates. That includes low voltages switches like power MOSFETs, which are on backorder for more than six months because of shortages.

To refill the supply chain, Infineon also said that it would maximize the 300-millimeter production capacity at its main factory located in Dresden, Germany. The Dresden fab originally manufactured 200-millimeter wafers, but it was converted to the larger diameter wafers almost two decades ago. That allowed the company to improve yields and slash costs.

The 300-millimeter manufacturing process was developed at Infineon’s Villach research laboratory before being deployed to the Dresden facility over the last two decades. Infineon said that the new 60,000-square-foot factory in Villach could potentially handle $2.1 billion in sales every year, with all the available capacity in use.

A major conundrum for the embedded industry is that while the cost of computer chips has fallen over the years, the design costs are growing. And increasingly, custom chips are required to drive up efficiency and drive down the size of connected devices, like smart thermometers that automatically adjust the temperature in a room and wristbands that track your health. 

But in recent years, several companies have been trying to reduce the costs and amount of time involved in traditional chip development. Mountain View, California-based zGlue has developed a programmable silicon interposer technology that allows multiple die to be combined onto a single chip, lowering the bar for what could be prohibitively costly custom chip design.

The 2.5D integration technology enables system-on-chips to be assembled the same way as one would put together a circuit board, and zGlue recently introduced a new product with its own custom chip at Maker Faire in San Francisco. The product, zOrigin, is designed for wearable devices but it can be adapted to other devices, such as smart jewelry and fitness bands.

zOrigin is the first product based on an SoC developed with zGlue's chip stacking technology, which allows designers to assemble chips from chiplets or tiny bits of circuitry that range from memory to microcontrollers to sensors. The product can be preordered for $149, and the SoC inside is smaller than a dime, measuring only 11 millimeters by 27 millimeters.

The company – whose business model could be called semiconductors-as-a-service – has raised $9.1 million in funding since it was founded by former chip architects from Samsung Electronics and Advanced Micro Devices in 2014. zGlue has developed software tools that make it easier for embedded engineers to drop die into its silicon interposer.

The interposer approach differs from system-in-package technology – more commonly known as SiP – in which chips are stacked vertically and stitched together by wires bonded to the packaging. That technique saves space but costs more. zGlue’s ZiP technology is designed to speed up development, allowing chips to be manufactured at volume in as little as two months, while slashing size by an order of magnitude.

The plan is to have a storefront where designers can select chiplets from companies like NXP Semiconductors, Maxim Integrated and the company’s other partners. As long as the appropriate chiplets are available, zGlue’s integration platform could help significantly cut the costs of creating custom chips for compact embedded devices – and make them more accessible to developers.

San Mateo, California-based startup SiFive has a similar strategy. The company provides support around the RISC-V architecture, making it easy to commission custom chips for Internet of Things devices, data centers and other applications. The company, which recently raised $50.6 million in venture capital, is expanding its DesignShare program to provide intellectual property that can be puzzled together in custom chips.

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Reliable sensing in an automobile can make a trip that much more enjoyable. Something as simple as a reliable door closure indicator can remove distractions while driving, or better yet, quickly indicate when the children’s back-seat door has opened. These instances certainly require latches, but equally as crucial as the fastener is having knowledge of closure.

It’s critical to select the proper sensor type—one that’s immune to the automobile’s environment—for the driver’s sanity. The automobile’s harsh environment, such as rich magnetic fields, vibration, dust, dirt, oil, or moisture, can cause the best of sensors to fail.

The act of sensing the closure of a door can seem like a simple proximity-sensing task. Proximity sensors detect an object without touching it, and they, therefore, don’t cause abrasion or damage to the object. The sensor candidates for this proximity-sensing task are the photodiode/LED pair, capacitor, and inductor.

Such a system sends an LED light in the direction of a photodiode. As the photodiode accepts the luminance of the LED light, a photodiode current, with predictable linearity, identifies the closeness of the LED. The capacitor sensor uses electrical fields to quantify the proximity of an object. The inductor, in combination with other inductors and a metallic material, uses exclusively magnetic fields to identify close-proximity events. The sensor accomplishes this by generating a signal in one inductive coil and sensing the reactive signal in the two other coils along, with the introduction of a magnetic plate.

So which sensor will provide the best, most reliable, repeatable, rugged results? As we close in on the best sensor, the best place to start is to define the automotive environment.

 Sponsored Resources:

• ZMID5201/02/03 Inductive Position Sensor IC
• Blog: Superior Alternatives to Magnetic Position Sensing
• ZMID5201 Inductive Position Sensing Starter Kit
• How To: Design Low-Cost Contactless Position Sensors

Automotive Environment

When it comes to electrical systems, this automotive environment is the worst of the worst. The automotive shell, frame, and interior are rampant with oil, moisture exposure, extreme shock, vibration, effects of explosive gases, and dust-laden environments. All of these elements create an extremely hostile micro-cosmos. And in this environment, the expectation is that the electrical systems operate failure-free.

Optical Proximity Sensor

The optical proximity sensor consists of an LED that’s ON, a photodiode, a transimpedance amplifier (TIA). and a light shield with a window. When the position of the LED causes light to shine on the photodiode (through the light shield), the photodiode generates current through the amplifier’s feedback resistor (Rf) (Fig. 1).

1. Optical proximity sensors tend to suffer from LED reliability and unclean environmental issues.

The proximity system in Fig. 1 has LED reliability and unclean environmental problems. In terms of the LED, the device luminance tends to decrease over time. The only solution to this problem is to replace the LED entirely.

Environmental cleanliness is, of course, a key factor—any debris in the space between the LED and photodiode will degrade the reception in this system. If the dirt and debris are chronic, the proximity system will cease to operate correctly. In addition to this environmental clutter, the alignment of the LED and photodiode is easily misaligned due to vibration and extreme shock.

Capacitive Proximity Sensor

A capacitive proximity sensor can detect and measure a different dielectric or conductive material between the plates. The capacitor sensor is able to measure proximity, position/displacement, humidity, fluid level, and acceleration. A capacitor sensor has two conductive plates separated by non-conductive material or dielectric. The dielectric is typically air, plastic, or ceramic. Figure 2 shows the simple model of a capacitor.

2. A capacitive proximity sensor detects and measures a different dielectric or conductive material between two plates.

The dielectric of a capacitive proximity sensor changes with oil, moisture exposure, and dust-laden environments. However, if the application calls for delta changes rather than absolute change, the capacitor sensor fairs very well. On the negative side, the sensor is sensitive to magnetic changes. With the automobile, these changes can be dramatic.

Inductive Proximity Sensor

An inductive proximity-sensor system detects absolute rotary or linear motion. An inductive position sensor provides an ac signal that determines the presence of metal objects, while providing absolute position information. This technology utilizes induction in a wire loop and eddy currents to detect the position of a metallic target that’s sliding or rotating above a set of printed-circuit-board (PCB) coils.

The three coils in this system consist of one transmitter coil and two receiver coils. With an inductive technology, the embedded sensing elements are PCB coils (Fig. 3).

3. This linear inductor PCB layout, reproduced from the ZMID520x Evaluation Kit User Manual, features three copper-trace coils arranged as a transmitter coil and two receiver coils.

The PCB has three copper-trace coils arranged as a transmitter coil and two receiver coils. In addition, the system uses a metallic target to modify the magnitude of the signals in the coils, where the target can be any kind of metal, such as aluminum, steel, or a PCB with a printed copper layer.

The transmitter coil’s signal induces a secondary voltage in the receiver coils, depending on the position of the metallic target above the coils. The two receiving coils sense the target’s position through the transfer of a magnetic signal and creation of eddy currents. The ZMID520X sensor IC (Fig. 3, again) then demodulates and processes the secondary voltages from the receiver coils.

The IC, which connects directly to the three sensing elements or PCB inductor coils, drives the first of three coils and an external capacitor to form an LC oscillator. The receiver coils pick up the oscillator's signal and generate a magnetic field within the transmit coil area (Fig. 4).

4. Shown are the linear PCB trace connections.

The three options available in the ZMID520x family have identical sensing inputs with differing output capability. The ZMID5201 produces an analog output providing a 100% position map with a voltage range from 250 to 4750 mV. The ZMID5202 produces a PWM output that delivers a 100% position map to a duty cycle of 5% to 95%. And the ZMID5203 has a 12-bit Single Edge Nibble Transmission (SENT) output. The SENT protocol conforms to SAE J2716, Revision 2. In addition, SENT Pause and CRC can be programmed according to SAE J2716, Revision 3.

With all devices, there’s a digital One-Wire Interface (OWI) pin for device communication and programming. The bidirectional OWI makes it possible to adjust the device’s operation, such as coil polarity, sine/cosine offset, and linearization for imperfect coils, and provides protection and error diagnostic capability.

The ZMID520x family is fully qualified to automotive standard AEC-Q100, grade 0 up to 150°C ambient temperature. 

Getting a Sense of Confidence

The inductive proximity-sensing system is rugged against all odds. When the technology is pitted against its optical and capacitive cousins, it outperforms them both.

This PCB/integrated-chip combination is immune to the automotive-rich magnetic fields, where high currents and the wiring harness generate magnetic fields to an unbearable level for most sensors. Beyond that, it’s immune to vibration, dust, dirt, oil, and moisture. This technology even endures excessively shocking events.

Inductive position sensing technology is paving new roads in the automotive industry, and IDT's ZMID520x family of devices brings value to the table by increasing the reliable, repeatable ruggedness of your automobile.

 Sponsored Resources: 

• ZMID5201/02/03 Inductive Position Sensor IC 
• Blog: Superior Alternatives to Magnetic Position Sensing
• ZMID5201 Inductive Position Sensing Starter Kit
• How To: Design Low-Cost Contactless Position Sensors

Discover the Rohde & Schwarz quick guide to power integrity. Our Power Integrity Infographic is a handy resource for verifying power rail tolerances, and includes common PI measurements, test equipment measurement challenges, power integrity probing methods, and more. Have the basics of power integrity at your fingertips.

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XP Power announced that it acquired power supply manufacturer Glassman High Voltage for $44.5 million, expanding its portfolio of power supplies used in applications such as chip manufacturing, medical diagnostics and test equipment. On Thursday, the power electronics supplier said that the acquisition would help expand its business in the industrial sector.

“Glassman fits directly with our strategy of growing our high power and high voltage capabilities to complete our product offering and expand our addressable market," said Duncan Penny, chief executive of XP Power, in a statement. The acquisition allows the company to “offer a full suite of products from miniaturized low power modules to high power rack mount high voltage solutions.”

The acquisition follows XP Power's acquisition of radio frequency power supply company Comdel in 2017 and Emco High Voltage Corporation in late 2015. Last year, the company established a new radio frequency division following the $23-million Comdel deal. XP Power shelled out around $12 million for Emco, which manufactures DC-DC converters primarily for industrial and medical electronics.

The goal of embedding our ubiquitous, silicon-based ICs with high-speed optical interconnects without need for intervening electro-optical conversion (and its complement) may be a step closer to reality. A team at MIT, headed by associate professor of physics Pablo Jarillo-Herrero, has devised a way to use a sophisticated material to bridge the gap, overcoming the impediments that naturally exist among silicon, light emission/capture, and optical wavelength

In their paper “A MoTe₂-based light-emitting diode and photodetector for silicon photonic integrated circuits” published in Nature Nanotechnology, along with extensive supplementary information, researchers at Massachusetts Institute of Technology detailed their demonstration efforts. The underlying materials problem is that silicon, despite its many wondrous electrical and mechanical properties, isn’t compatible with optical requirements. Most semiconductor materials emit light in the visible range, and silicon absorbs light at these wavelengths. 

They developed a silicon waveguide-integrated light source and photodetector based on a P-N junction of bilayer molybdenum ditelluride (MoTe₂), which is an ultrathin semiconductor in a group of materials known as two-dimensional transition-metal dichalcogenides (TMDs). MoTe₂ emits light in the infrared range, and thus isn’t absorbed by silicon. Therefore, it can be used for on-chip communication.

1. Sketch of a device based on encapsulated monolayer MoTe₂, with separation of the split metal gates is 200 nm; the flake width is about 5 μm (a). Optical image of the monolayer device before the source-drain metal electrodes evaporation (b). (Source: MIT and Macmillan Publishers Limited/Springer Nature)

To use the material as a light emitter, the researchers first had to convert it into a P-N junction diode, which is done by introducing chemical impurities into the substrate material. In contrast, the 2D molybdenum ditelluride can be mechanically attached to any material; then a voltage is applied across metallic gate electrodes placed side-by-side on top of the material (Fig. 1). Prof. Jarillo-Herrero notes, “So by using diodes made of molybdenum ditelluride, we are able to fabricate light-emitting diodes (LEDs) compatible with silicon chips.”

The device can also be configured to function as a photodetector by reversing the polarity of the voltage applied to the device. This causes it to stop conducting electricity until light shines on it, at which time the current flow resumes. In this way, the devices are able to both transmit and receive optical signals.

The research team believes that these emerging two-dimensional TMDs could provide an approach to developing optical interconnect components that could integrate with silicon photonics and CMOS processing (Fig. 2). Most telecommunication systems operate at optical wavelengths of 1.3 or 1.5 μm, while molybdenum ditelluride emits light at 1.1 μm. This makes it compatible with silicon ICs, but not a fit for telecommunications systems. For this reason, 1.3-/1.5-μm emission and detection wavelengths would simplify fabrication of optical-fiber links.

2. The experimental setup used for measuring the time response of the p-n junction (a); photoresponse of bilayer MoTe₂ p-n junction used to modulated the laser at 1 MHz (b); details of the rising (c) and falling edges (d); frequency response of the test setup’s transimpedance amplifier, with 3-dB rolloff near 150 MHz (e). (Source: MIT and Macmillan Publishers Limited/Springer Nature)

To achieve this, the researchers are investigating black phosphorus, an ultrathin material that can be “tuned” to emit light at different wavelengths by changing the number of layers of material used. By doing so, they hope to develop devices with the number of layers needed to emit light at those two wavelengths yet retain the compatibility with silicon.

Jarillo-Herrero acknowledged that the results of the research, which was supported by the Center for Excitonics (an Energy Frontier Research Center funded by the U.S. Department of Energy), are a proof of concept and far from commercialization. Nonetheless, “the hope is that if we are able to communicate on-chip via optical signals instead of electronic signals, we will be able to do so more quickly, and while consuming less power,” he added.

Most engineers have known for years that microcontrollers are the best choice in building new digital products. Legacy TTL and CMOS functional logic devices gave way to single-chip MCUs years ago. Yet some operations are still implemented with fixed-function devices because an MCU seems like expensive overkill in certain cases. Not anymore, though. When the price for a tiny MCU comes down to pennies, it’s time to reconsider the use of fixed-function circuits. Here are some ideas to help you go in that direction.

Design Examples

A cheap MCU can replace more discrete logic and mixed-signal devices than you think. One example is a two-bit 8-bit microcontroller that’s able to replace the still popular 555 timer IC. But that’s not all. There are four basic areas where an inexpensive MCU can replace a fixed-function device: communications, system housekeeping, pulse-width modulation (PWM), and timing. The examples below illustrate how it can be done.

Communications

In terms of communications, one example involves the need for two devices to talk to one another. One device uses a UART for external serial communications and another employs a serial peripheral interface (SPI). What’s required is a bridge that acts as a translator for the two devices (Fig. 1). The MCU code translates the protocol of one serial method to another and provides data buffering and half-duplex data transfers. The ability to program the device lets you change the design to optimize it for your application.

1. Here, the MCU acts as a UART-to-SPI bridge.

Another communication application example concerns the use of a single bidirectional line to transfer data between the MCU and a master device. Commonly referred to as 1-wire or SDQ single-wire serial interfaces, this communication peripheral reduces the number of physical hardware connections required while adhering to a protocol that’s easily achievable with a simple MCU. This simple interface is used with external EEPROMs, SHA-1 authenticators, temperature sensors, digital switches, and battery-system monitors.

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Most engineers have known for years that microcontrollers are the best choice in building new digital products. Legacy TTL and CMOS functional logic devices gave way to single-chip MCUs years ago. Yet some operations are still implemented with fixed-function devices because an MCU seems like expensive overkill in certain cases. Not anymore, though. When the price for a tiny MCU comes down to pennies, it’s time to reconsider the use of fixed-function circuits. Here are some ideas to help you go in that direction.

Design Examples

A cheap MCU can replace more discrete logic and mixed-signal devices than you think. One example is a two-bit 8-bit microcontroller that’s able to replace the still popular 555 timer IC. But that’s not all. There are four basic areas where an inexpensive MCU can replace a fixed-function device: communications, system housekeeping, pulse-width modulation (PWM), and timing. The examples below illustrate how it can be done.

 Sponsored Resources: 

• Enhance simple analog and digital functions for $0.25
• 25 functions for 25 cents video series
• 25 functions for 25 cents introduction

Communications

In terms of communications, one example involves the need for two devices to talk to one another. One device uses a UART for external serial communications and another employs a serial peripheral interface (SPI). What’s required is a bridge that acts as a translator for the two devices (Fig. 1). The MCU code translates the protocol of one serial method to another and provides data buffering and half-duplex data transfers. The ability to program the device lets you change the design to optimize it for your application.

1. Here, the MCU acts as a UART-to-SPI bridge.

Another communication application example concerns the use of a single bidirectional line to transfer data between the MCU and a master device. Commonly referred to as 1-wire or SDQ single-wire serial interfaces, this communication peripheral reduces the number of physical hardware connections required while adhering to a protocol that’s easily achievable with a simple MCU. This simple interface is used with external EEPROMs, SHA-1 authenticators, temperature sensors, digital switches, and battery-system monitors.

Pulse-Width Modulation

Most low-cost MCUs include PWM capability. PWM generates a variable pulse duration and duty cycle. These output pulses can be easily averaged into a proportional dc with external low-pass RC filters. The PWM function can also serve as a simple digital-to-analog converter (DAC). Among the many applications are LED dimming or color change, servo- or stepper-motor control, signal generation from a lookup table, or other analog-related functions. Figure 2 shows the necessary external RC filters for most uses.

2. External low-pass filters create analog and DC outputs from PWM signals.

Housekeeping

Many possibilities exist for system and housekeeping functions. Here are just a few examples:

• EEPROM emulation using the MCU’s non-volatile memory
• Low-power hex keypad
• Multifunction reset controller
• Single-slope analog-to-digital conversion
• ADC Wake and Transmit on Threshold
• Hysteresis comparator
• Programmable frequency-locked loop
• Programmable clock source

Figure 3 shows how the non-volatile ferroelectric RAM in an inexpensive MCU can replace EEPROM that’s often needed in certain applications. The EEPROM is used to store boot information, identification codes, backup data, calibration data, and other data that must be retained when power is off. The inexpensive FRAM MCU is connected via a SPI interface with traditional control signals.

3. An MCU with FRAM does a good job of emulating needed external EEPROM.

Timing

Timing functions offer many other possibilities. Examples are simple kitchen timer, a stopwatch, a watchdog timer, or real-time clock. An internal 32-kHz reference oscillator, if available, can provide the timer accuracy, and an external crystal clock can be used for high-precision requirements. Internal timer counters accumulate the clock pulses.

Figure 4 shows a stopwatch example. Stop-start and reset buttons provide the external control. A 7-segment LED display shows the output. General-purpose digital I/O pins on the MCU accept the inputs and generate the outputs. External transistors are needed to control the multiplexed LED display.

4. An inexpensive MCU makes a simple and inexpensive stopwatch.

What’s discussed above represents only a few instances of how a cheap MCU can solve some interface problems. You know the value of programmability, and now you can apply that to simple functions when the cost is right.

Texas Instruments has produced an eBook that illustrates the many application possibilities of low-cost MCUs. The eBook includes brief application reports and links to code examples to get you started, as well as tips for code optimization.

Selecting the Right MCU

Literally dozens of inexpensive MCUs are available to implement external functions like those described here. One family of devices that not only meets the low-cost ($0.25) target but also provides significant software support to make these MCUs easy to use is the ultra-low-power MSP430 microcontrollers (MCUs) from Texas Instruments.

These 16-bit MCUs feature a RISC architecture, on-chip RAM, and TI’s ferroelectric non-volatile RAM. Clock rate can be up to 16 MHz, and I/O consists of GPIO pins, I²C, SPI, and UART interfaces. PWM capability and multiple timers add more versatility. All versions have a comparator with programmable hysteresis and a 10-bit ADC. The design is optimized for very low power operation. Multiple versions are available with 16- or 24-pin package options. A variety of evaluation boards and software development products provide design support.

More Information Waiting for You

Texas Instruments has plenty of additional data on the use of low cost MCUs. Check out their “25 functions for 25 cents” video series to see some examples of the simple analog and digital functions that can be replaced by low-cost MSP430 MCUs. Also, check out this blog that provides additional examples.

 Sponsored Resources: 

• Enhance simple analog and digital functions for $0.25
• 25 functions for 25 cents video series
• 25 functions for 25 cents introduction