Tag Archives: picopower

Designing the future of touch with Atmel

Atmel CEO Steve Laub probably put it best when he told the Wall Street Transcript that touch is generally considered to be the preferred method for current-gen consumers to interface and interact with electronic devices.

“For the last three years, [Atmel has] been the world’s leading provider of mobile touch solutions, so our technology and products are changing the way people use and interact with electronic [devices],” Mr. Laub explained. “Our technology is also changing how they view the world and the ability to interact with the world.”

Indeed, Atmel has achieved a number of impressive milestones in the touch space over the last 6 months including:

XSense: A high-performance, highly flexible touch sensor which allows engineers to design devices with curved surfaces and even add functionality along product edges. Atmel is now positioned to ramp volume production for this revolutionary new tech.

Facilitating an uber-thin wireless touch interface: Cambridge Silicon Radio (CSR) developed an uber-thin wireless touch interface. The flexible interface, measuring less than 0.5 mm thick, turns any area into a touch surface for mobile devices and even desktops. To create the ultra-thin wireless touch surface, CSR partnered with Atmel and Conductive Inkjet Technology (CIT). More specifically, the device uses Atmel’s touch silicon tech to sense multiple contact points on a surface – and is therefore capable of offering a full touch surface or power optimized key detection.

Expanding the maXTouch auto lineup: In July, Atmel rolled out a new maXTouch family to facilitate single-layer shieldless designs in automotive center stacks, navigation systems, radio interfaces and rear seat entertainment platforms. The mXT336S is optimized for 7-inch touchscreens, while the mXT224S targets smaller touchscreens and tablets.

Powering the Samsung Galaxy S4 Mini’s touchscreen: Samsung selected Atmel’s maXTouch mXT336S controller to power the touchscreen of its Galaxy S4 Mini.

Powering Samsung’s Galaxy S4: The Galaxy S4 is fitted with Atmel’s sensor hub management MCU (microcontroller unit) which collects and processes data from all connected sensors in real-time, optimizing multiple user experiences, such as gaming, navigation and virtual reality. In addition, the sensor hub MCU lowers the overall system power consumption via picoPower technology to prevent drain and enable longer battery life.

Driving Asus touchscreens: Asus selected Atmel’s mXT2952T and mXT1664T controllers to drive the touchscreens of multiple new tablets and Ultrabooks – including the Zenbook Infinity which is based on Intel’s Haswell processor.

Enabling ‘in-cell’ touch for custom LCD designs: AndersDX introduced In-Cell Touch technology custom liquid crystal display (LCD) installations targeted at low- to high-volume consumer manufacturing. Instead of a touch sensor bonded onto the LCD display, each In-Cell touch key is embedded directly into the LCD cell. The LCD ITO pattern is then designed to match individual touch key symbols. An Atmel Q Touch sensor IC integrated into the display electronics controls up to four touch keys per application.

Outdoors with Ocular: Atmel’s maXTouch S trekked to the great outdoors with Ocular LCD’s PCAP touch panels. Designed specifically for outdoor and marine applications, these Crystal Touch panels are non-birefringent and immune to false touches caused by water spray and droplets.

Atmel’s AVR XMEGA MCU: High integration and ultra-low power

Earlier this week, Bits & Pieces took a close look at Atmel’s AVR UC3 which is built around high-performance 32-bit AVR architecture and optimized for highly integrated applications. Today, we are getting up close and personal with Atmel’s AVR XMEGA, an MCU designed for real-time performance, high integration and ultra-low power.

Powered by an Atmel AVR CPU, the AVR XMEGA is tuned to minimize code size and maximize execution speed. Indeed, its true single-cycle execution of arithmetic and logic operations allows AVR XMEGA microcontrollers to perform close to 1 MIPS per MHz. The fast-access register file with 32 x 8-bit general-purpose working registers is directly connected to the arithmetic logic unit (ALU). During a single clock cycle, the ALU can be fed two arbitrary registers, do a requested operation and write back the result. It provides efficient support for 8-, 16-, and 32-bit arithmetic. Plus, 12-bit analog-to-digital converters (ADCs) with gain stage offer a combined throughput of 4MSPS, while fast 12-bit digital-to-analog converters (DACs) with high drive strength, as well as other functions, reduce the need for external components.

As noted above, the AVR XMEGA boasts real-time performance, with an Event System that facilitates inter-peripheral signaling with 100% predictable response time. To help offload the CPU, all peripherals can use direct memory access (DMA) for data transfer. Meanwhile, Atmel’s stalwart picoPower technology enables true 1.6V operation, down to 100nA RTC operation with full SRAM retention for fastest possible wake-up time.

“In terms of integration, AVR XMEGA devices include Advanced Encryption Standard (AES) and Data Encryption Standard (DES) crypto modules, up to 32 pulse-width modulation (PWM) outputs, 8 UARTs, 4 TWI (I2C) and 4 serial peripheral interface (SPI) channels, a cyclic redundancy check (CRC) generator module and more,” an Atmel engineering rep told Bits & Pieces.

“On the USB connectivity side, the AVR XMEGA delivers full-speed operation without the need for external crystals, 31 endpoints, along with a special multi-packet function that maximizes data transfer rates while minimizing CPU load.”

AVR XMEGA devices also feature an innovative XMEGA  consisting of two independent 8-bit timers/counters and two lookup tables used for defining glue logic. It is designed to reduce bill of material (BOM) and PCB size as the XCL can replace external circuitry such as delay elements, RS-latches, D-latches, D-flip-flops chip-select logic, AND, NAND, OR, NOR, XOR, XNOR, NOT, MUX AND/OR/XOR logic gates. In addition, it can, in conjunction with the USART, enable customized communication protocols.

And last, but certainly not least, Atmel’s AVR Software Library include a plethora of device drivers and communication stacks that save time and development effort, allowing engineers to focus on more important design tasks. Similarly, Atmel’s QTouch Sensing Library helps devs to easily integrate robust capacitive touch sensing interfaces for buttons, sliders and wheels.

Interested in learning more? Additional Atmel AVR XMEGA technical details are available here.

Designing gas and water meters with Atmel MCUs

Gas and water meters – deployed by utility companies to measure usage stats – are typically designed to display data on a small segment LCD screen. Unlike standard electricity meters, gas and water meters are usually battery-operated, so power efficiency is clearly a key requirement.

RF communication has also become a critical feature for gas and water meters due to the advent of AMI architecture – with the Smart Electricity Meter often acting as the gateway to a utility for meter reading. In addition, an increasing number of gas and water meters are tapping into home area networks, requiring optimized security to protect data communications between devices.

The microcontrollers used in gas and water meters are generally 8- or 16-bit MCUs with ultra-low power features, often with integrated LCD segment drive capability. As such, selecting Atmel’s extensive MCU portfolio to design water and gas meters offers engineers a number of advantages.

“These include potentially best-in-class embedded 12-bit ADC and analog comparators to provide analog peripheral support, 1 µA watchdog and brown-out (monitor), picoPower to extend battery life, an event system to facilitate measurement whilst CPU is in SLEEP modes, 1.6V operation and lowest power 32 kHz crystal oscillator (650nA RTC),” an Atmel engineering rep told Bits & Pieces.

“There is also an option for embedded display controller, with high EMC performance reducing the need for external protection. Meanwhile, ±1% internal oscillators enable communications to run from internal oscillator (RC), as hardware authentication products with ultra-low standby current coupled with onboard microcontroller encryption enhances security for networked applications. In terms of transceivers, Atmel RF Transceivers offers best-in-class power consumption, while our single-chip Atmel ATmega128RFA1 combines a microcontroller and RF transceiver for efficient BOM.”


Unlike electricity measurement (voltage/current), notes the engineering rep, gas and water meters utilize a variety of parameters and techniques for flow metering. Examples include turbine and pelton wheel, optical acoustic doppler, thermal mass, vortex, magnetic, ultrasonic and coriolis flow meters (see the metrology sensor, shown in the block diagram above).

Analog-to-Digital Converters (ADC) and Digital-to-Analog (DAC) can also be useful peripherals to embed in the microcontroller, as they help facilitate flow measurement. Remember, flow meters are battery-powered, requiring power-efficient solutions capable of supporting up to 20 years of operation.

“Of course, LCD support is an important requirement. This capability can be driven serially with chip on glass, but must often be integrated into the microcontroller. Essential peripherals include serial communications and, frequently, security through encryption,” the engineering rep added.

“Dual clock input for high accuracy main clock (often used for timings in metrology) and second clock input for 32KHz for RTC. For Smart Meter and Smart Grid implementations, RF is the communication medium of choice to connect to the HAN to support AMR.”

Interested in learning more about using Atmel MCUs to design gas and water meters? Be sure to check out our extensive portfolio of MCUs that can be used to power such designs.

Low-power design in the age of IoT

Facilitating low-power designs for electronic devices is more important than ever before as we move toward a world dominated by the Internet of Things (IoT).

Essentially, the IoT refers a future scenario in which all types of electronic devices link to each other via the Internet. Today, it’s estimated that there are nearly 10 billion devices in the world connected to the Internet, a figure expected to triple to nearly 30 billion by 2020.

The challenge? Reducing power consumption (to extend battery life) while simultaneously maintaining acceptable levels of performance. Fortunately, Atmel has been focusing on low power consumption for more than ten years across its extensive portfolio of AVR and ARM-based microcontrollers and embedded microprocessors.

Design techniques employed to achieve the critical balance between power consumption and performance include:

  • Use of hardware DMA and event system to offload the CPU
  • Cut clock or supply on device portions not in use
  • Careful balance of high performance and low leakage transistors
  • Fast wake up from low power modes
  • Low voltage operation

“With the Atmel picoPower technology found in our AVR 8-bit and 32-bit microcontrollers, we’ve even gone one step further. All picoPower devices are designed from the ground up for lowest possible power consumption – all the way from transistor design and process geometry, to sleepmodes and flexible clocking options,” an Atmel engineering rep told Bits & Pieces.

“Atmel picoPower devices can operate down to 1.62V while still maintaining all functionality, including analog functions. They have short wake-up time, with multiple wake-up sources from even the deepest sleep modes.”

Although certain elements of picoPower tech cannot be directly configured by the user, they do form a solid base that facilitates ultra-low-power application development without compromising functionality. On the user level, flexible and powerful features and peripherals allow engineers to more easily apply a wide range of techniques to reduce a system’s total power consumption even further. As expected, picoPower technology is also relatively simple to deploy, with both basic and advanced techniques reducing the power consumption of an application even further.

A perfect example of Atmel’s commitment to low-power devices is the 0.7V tinyAVR. Remember, a typical microcontroller requires at least 1.8V to operate – while the voltage of a single battery-cell ranges from 1.2V to 1.5V when fully charged, dropping gradually below 1V during use (yet still holding a reasonable amount of charge). This means the average microcontroller requires at least two battery cells.

“We have solved this problem by integrating a boost converter inside the ATtiny43U, converting a DC voltage to a higher level and bridging the gap between minimum supply voltage of the microcontroller and the typical output voltages of a standard single cell battery,” the Atmel engineering rep explained. “The boost converter provides the microcontroller with a fixed supply voltage of 3.0V from a single battery cell even when the battery voltage drops down to 0.7V.”

Simply put, this extends battery life by allowing non-rechargeable batteries to be drained to the minimum, while programmable shut-off levels above the critical minimum voltage level avoid damaging the battery cell of rechargeable batteries.

Interested in learning more about Atmel’s low-power, high performance portfolio? Be sure to check out our extensive ARM and AVR product lineups here.

Atmel’s maXTouch powers Galaxy S4 Mini’s touchscreen

Samsung has selected Atmel’s maXTouch mXT336S controller to power the touchscreen of its recently launched Galaxy S4 Mini.

Powered by a 1.7GHz dual-core processor and running Google’s Android 4.2.2 operating system, the Samsung Galaxy S4 Mini also boasts a 4.3-inch high-definition super AMOLED display.

“The mXT336S controller delivers the ultimate human touch interface with its feature-rich solution by enabling thinner stylus and thicker glove support,” an Atmel spokesperson told Bits & Pieces. “It also facilitates more touch precision and fewer unintended touches, along with lower power consumption for longer battery life, brighter displays and faster response times.”

Additional key Galaxy S4 Mini features include:

  • 4G LTE in addition to 3G and 3G dual-SIM versions
  • 8-megapixel rear camera and recording
  • 1.9-megapixel front-facing camera
  • 1.7GHz dual-core processor
  • 1,900 mAh battery

It should be noted that Atmel technology can be found in a number of Samsung mobile devices, including the full-sized Galaxy S4. As previously discussed on Bits & Pieces, the Galaxy S4 is fitted with Atmel’s sensor hub management MCU (microcontroller unit) which collects and processes data from all connected sensors in real-time, optimizing multiple user experiences, such as gaming, navigation and virtual reality. In addition, the sensor hub MCU lowers the overall system power consumption via picoPower technology to prevent drain and enable longer battery life.

A closer look at Atmel’s picoPower technology

We briefly touched on Atmel’s picoPower technology this morning in the context of Samsung’s Galaxy S4 smartphone, which is equipped with Atmel’s sensor hub management MCU (microcontroller unit). The MCU collects and processes data from all connected sensors in real-time, optimizing multiple user experiences, such as gaming, navigation and virtual reality.

Atmel’s sensor hub MCU also lowers the overall system power consumption via picoPower technology to prevent drain and enable longer battery life. In a broader sense, it is important to note that all Atmel AVR picoPower devices are designed from the ground up for low power consumption utilizing the company’s proprietary low leakage processes and libraries to provide minimal power sipping in all sleep modes.

“An easy way to reduce power consumption in any design is to lower the operating voltage. But this would be mostly useless if analog performance was compromised,” an Atmel engineering rep told us. “Central to the AVR picoPower technology are carefully designed analog functions that continue to operate all the way down to 1.62V.”

To be sure, the various features of a microcontroller traditionally become unstable or even unusable at different voltage levels, as inaccuracies in analog peripherals, limited operation or an inability to write to non-volatile memory prevents designs from running at lower voltages. This leads to shorter battery life, larger and more expensive batteries, or a lot time spent trying to find workarounds for something that should be addressed by the microcontroller to begin with.

As such, Atmel AVR microcontrollers offer true 1.62 V operation, including all analog modules, oscillators, and flash and EEPROM programming. Meaning, various microcontroller features will not shut down one by one as the voltage drops.

“You can run the same application at different voltages without making comprises. All peripherals are available regardless of supply voltage,” the engineering rep continued. “The ADC, for example, can be used to measure the supply voltage as the cutoff voltage is approached, and when detected, it enables the application to store vital information and ensure a safe shutdown, enabling a glitch-free restart after changing batteries.”

Remember, power consumption is proportional to supply voltage, so running at as low a supply voltage as possible saves power. For battery operated devices, the Atmel AVR microcontroller can make use of the remaining power available at lower battery voltage levels as the battery depletes.

In addition to true 1.62 V operation, Atmel’s AVR peripherals with picoPower are capable of determining if incoming data requires use of the CPU or not. This feature is aptly dubbed SleepWalking, as it allows the CPU to sleep peacefully until an important event occurs, eliminating millions of false CPU wakeups. This means the CPU is no longer required to check whether or not a specific condition is present, such as an address match condition on the TWI (I2C) interface, or a sensor connected to an ADC that has exceeded a specific threshold.

Of course, entering sleep mode shuts down parts of the microcontroller to save power. Most oscillators and clocks consume a considerable amount of power when in use, and when waking up from sleep modes, these clocks need to be stable before they can be used. Waiting a long time for the clocks to be available and stable results in wasted power.

However, the Atmel AVR microcontroller is capable of waking up from sleep mode in 8 clock cycles when running from the internal RC oscillator. Moreover, a digital frequency locked loop (DFLL) replaces the traditional phase locked loop (PLL) to provide a programmable internal oscillator that is much faster and accurate.

It can also eliminate external components, which reduces the total system power consumption even more. When in sleep mode with the synchronous clocks turned off, the microcontroller can still wake up from asynchronous events such as a pin change, data received or even an I2C bus address match – enabling multiple wake-up sources from even the deepest sleep modes.

As noted above, the benefits of picoPower are clearly illustrated by Samsung’s decision to equip its flagship Galaxy S4 smartphone with Atmel’s sensor hub MCU which features picoPower tech.

“Atmel allows Galaxy S4 users the ability to enjoy applications requiring real-time motion sensing, without ever compromising battery life,” said Ingar Fredriksen, Senior Director of Flash-based Microcontrollers, Atmel Corporation. “ We look forward to teaming with Samsung on future designs.”

Samsung’s Galaxy S4 is equipped with Atmel’s sensor hub MCU

The Galaxy S4 is currently Samsung’s flagship Android-powered smartphone. The slick device is equipped with a 4.99-inch touchscreen with full 1080p resolution, 2600 mAh battery, quad-core processor and a 13-megapixel dual-shot camera.


Since the Galaxy S4 is a next-gen handset, the smartphone boasts increased awareness of its environmental surroundings via a number of advanced sensors, including an accelerometer, RGB light, digital compass, proximity, gyro and a barometer.

The Galaxy S4 is also fitted with Atmel’s sensor hub management MCU (microcontroller unit) which collects and processes data from all connected sensors in real-time, optimizing multiple user experiences, such as gaming, navigation and virtual reality. In addition, the sensor hub MCU lowers the overall system power consumption via picoPower technology to prevent drain and enable longer battery life.

“Samsung’s new Galaxy S4 illustrates how motion sensing is an important function in the new device,” explained Ingar Fredriksen, Senior Director of Flash-based Microcontrollers, Atmel Corporation. “With a sensor hub management solution, Atmel allows Galaxy S4 users the ability to enjoy applications requiring real-time motion sensing, without ever compromising battery life.”

Meanwhile, Sueng-jun Park, Senior Engineer, Samsung Electronics, noted that the company’s customers have come to expect the ultimate experience from the flagship lineup of Galaxy smartphones.

“For that reason, we selected the Atmel sensor hub MCU to ensure the motion-related applications, including gaming, navigation and virtual reality, are hyper sensitive to real-time direction and orientation,” he added.

How low is low power?

A buddy called up asking me the minimum power consumption of Atmel chips. He has an application that has to be battery powered and it just can’t suck much more than the self-discharge out of the battery. I had another application years ago with the similar problem. I was trying to steal power from a phone line to run a little micro. If you look at the very strict laws, you are only allowed about a microampere out of the -48V POTS (plain-old-telephone-system) line.

So the trick is to steal the microampere continually, and let it charge up a big capacitor, so your micro has more than a few uA to run on for a little while. My buddy had a pretty high battery voltage. So with a switching power supply he can take in 1 uA at 24V and make 10uA at 2V that will power the MCU. Better yet, you can put the system to sleep or all the way into power-down, and only wake it now and then. With a 1% duty cycle, your 10uA continuous current can instead become 1mA when you are in wake mode and 0.1uA the other 99% of the time.

So back to the task of figuring just how low a low-power AVR chip is. Since this is a hardware issue, and you only have to worry about hardware once in your design, the salient info is towards the end of the datasheet. And you do have to dig up the “full” datasheet, not the summary version. CMOS microprocessors use power in direct relation to the clock frequency they are operated at, as well as the power supply voltage you run them on.

So I started with the smallest physical part we make, the ATtiny13A . It is fully static. On page 126 they actually have a 2-dimentional power consumption graph, but the first one shows 100k-1MHz active clock. Scroll down to page 127, and Figure 19-6 shows 32kHz clock figures. The part sips about 7uA at 2V Vcc. Then scroll down for idle power—Figure 19-12, it’s about 1.2uA. Then more scrolling and you get a power-down consumption of 0.1uA with no watchdog, and 3uA with the watchdog.


My suggestion is to let the switching power system run the show. Have it gently steal power and when it has charged up a big ol’ ceramic cap, then have the power system take the MCU out of power-down, (not idle) do the measurement, and either kill itself or handle the alarm. This part does have a 10-bit ADC so you have to look at the time it takes to get a good conversion out of it.

This can get really tricky. My buddy Nick Gray noted that sometimes you are better using a faster ADC since you can get a good conversion out of it in less time, so the duty cycle of “on” goes down, and you end up using less power despite having a higher-current ADC. Same deal here— you need to think in Coulombs—what is the fewest number of electrons needed to wake up, do a test, and go back to sleep.

In any event, it is obvious that you can set up an AVR system to draw less than the self-discharge rate of your battery system. Note that if you need to do 500MHz processing, well all bets are off. The speed-power tradeoff in semiconductor devices is pretty absolute, so don’t think you can do HD video on a uA.

Intelligent MCUs for Low Power Designs

By Florence Chao, Senior Field Marketing Manager, MCU Business Development

Industrial and consumer devices using ARM® Cortex®-M4

Industrial and consumer devices using ARM® Cortex®-M4

Blood glucose meters, sport watches, game controllers and accessories, guess what they all have in common. Yes, like a lot of other industrial and consumer devices, they run on batteries and demand long or extended battery life. As an engineer, this translates into a key challenge when designing an embedded computing system. You need a central heart—in this case a microcontroller—that consumes as little power as possible in both active and static modes yet doesn’t sacrifice performance.  The Atmel® SAM4L ARM® Cortex®-M4 based series is designed with this in mind.

The SAM4L microcontroller redefines low power, delivering the lowest power consumption in its class in active mode (90uZ/MHz) as well as in static mode with full RAM retention running. It also delivers the shortest wake-up time (1.5us). At the same time, this is the most efficient microcontroller available today, achieving up to 28 CoreMark/mA.

The SAM4L series integrates Atmel’s proprietary picoPower® technology

The SAM4L series integrates Atmel’s proprietary picoPower® technology

The SAM4L series integrates Atmel’s proprietary picoPower® technology, which ensures the devices are developed from the ground up—from transistor design to clocking options—to consume as little power as possible. In addition, Atmel Sleepwalking technology allows the peripherals to make intelligent decisions and wake up the system upon qualifying events at the peripheral level.

In this video, you will see how the SAM4L microcontroller supports multiple power configurations to allow the engineer to optimize its power consumption in different use cases. You will also see another good feature of the SAM4L series, Power Scaling, which is a technique to adjust the internal regulator output voltage to further reduce power consumption provided by the integrated Backup Power Manager Module. In addition, the SAM4L series comes with two regulator options to supply system power based on the application requirement. While the buck/switching regulator delivers much higher efficiency and is operational from 2 to 3.6V. The linear regulator has higher noise immunity and operates from 1.68 to 3.6V.

The Atmel® SAM4L ARM® Cortex®-M4 based Microcontroller

The Atmel® SAM4L ARM® Cortex®-M4 based Microcontroller

It’s all about system intelligence and conserving energy. Simply put, the SAM4L microcontroller is your choice if you are designing a product that requires long battery life but you don’t want to sacrifice performance.  To get started, learn more about Atmel SAM4L Xplained Pro Evaluation and Starter Kits.

What’s new in Atmel’s ARM MCU? picoPower!!

The SAM4L it is the first ARM device to feature Atmel’s picoPower technology, and takes low power to a new level.   There are many different characteristics that make a low power device; foremost it is the active power, the wake-up time and sleep mode power consumption. For the SAM4L, this can go down to 90 µA/MHz in active, down to 700 nA in sleep mode and down to 1.5 µs wake-up. Additionally the Cortex-M4 and Atmel’s fast flash technology allows your application to spend a shorter amount of time in active and spend more time in low power modes. All of this significantly reduces the total power consumption for your application.

picopower explained

Atmel SAM4L MCUs redefine the power benchmark, delivering the lowest power in both active (90uA/MHz) and sleep
modes (1.5uA with full random access memory (RAM) retention and 700nA in backup mode). They are the most efficient
MCUs available today, achieving up to 28 CoreMark™/mA using the IAR Embedded Workbench, version 6.40.

Check out this video for more information about picoPower in the SAM4L.  Also, please be sure to follow us on this blog to learn more on how these ARM devices become so power conscious and other neat application tutorials.  Or share, collaborate, and innovate with the other tens of thousands of engineers/builders in the vibrant AT91 community.