Micro-electro-mechanical technology has revolutionized sensors and enabled hitherto unseen, highly integrated design solutions. We round up nine recent offerings in this arena.
This month, we’re excited to bring you some of the latest in micro-electro-mechanical systems (MEMS) sensors. Staying at the forefront of sensor technology is essential to many solutions. In this column, we’ve curated a selection of nine newer MEMS sensor products that could potentially transform your next project.
MEMS technology continues to grow in popularity for sensing applications for a variety of reasons. Primarily, MEMS sensors are extremely sensitive. They also have an especially low power consumption. And MEMS tech is highly scalable in manufacturing—which means a very low-cost for mass-produced devices. Further, by design they can be readily integrated with microelectronics, producing outcomes that are true “systems.” And of course, their size can be leveraged to achieve designs not possible at larger scales.
Meanwhile, like any embedded technology, AI technology has revolutionized how we use sensors to gather data from the world around us, analyze it to make decisions, and connect to a vast, broader network of intelligence systems to enable new solutions. This means numerous market opportunities for existing companies and start-ups, as well as an overabundance of existing niche options for the embedded systems developer already on the marketplace today.
The applications for MEMS sensors is limitless, from entertainment, transportation, medical applications, to the industrial Internet-of-Things (IIoT)—virtually anywhere you can imagine. As an example: accelerometers have been used extensively in automobiles, robotics, ships and even space exploration. More recently, thanks in part to the shrinking size of sensing tech, their use has spread to smartphones and wearables, opening up a whole world of interfacing with motion.
Whether pressure sensors, gyroscopes, high-precision accelerometers, thermal sensors, or environmental sensing units that integrate multiple types of sensors, there’s a huge wealth of MEMS sensor options available to developers today. Necessarily, this column represents the tiniest (pun intended) sliver of available offerings. Nevertheless, I hope you find inspiration in the following gallery.
Ultralow Power 3-Axis Accelerometer
The ADXL367 is an ultralow power, 3-axis microelectromechanical systems (MEMS) accelerometer that consumes only 0.89µA at a 100Hz output data rate and 180nA when in motion-triggered wake-up mode. Unlike accelerometers that use power duty cycling to achieve low power consumption, the ADXL367 does not alias input signals by undersampling, but samples the full bandwidth of the sensor at all data rates. The ADXL367 always provides 14-bit output resolution. 8-bit formatted data is offered for more efficient single-byte transfers when a lower resolution is sufficient. 12-bit formatted data is also provided for ADXL362 design compatibility. Measurement ranges of ±2g, ±4g, and ±8g are available, with a resolution of 0.25mg/LSB on the ±2g range.
- Supply voltage range: single-cell battery operation—1.1V to 3.6V; internal power supply regulation for high PSRR
- Ultralow power
- High resolution: 0.25mg/LSB
- Built-in features for system level power savings
- Low noise to 170µg/√Hz
- Acceleration sample synchronization via external trigger
- On-chip temperature sensor
- Internal two-pole anti-alias filter
- SPI (4-wire) and I2C digital interfaces
Ultra-Low Power Smart Sensor System
The BHI380 is a highly integrated, ultra-low power, customizable smart sensor system consisting of a best-in-class 6-axis IMU, a programmable 32-bit microcontroller (Fuser2 Core), a second ultra-low power MCU, with a power software framework containing pre-installed sensor fusion and other sensor data processing software within a 2.5mm x 3mm LGA package, pin-to-pin backward compatible with Bosch Sensortec IMUs. The BHI380 is a variant from the BHI3xx family featuring a larger set of integrated application-specific algorithms.
- 1.8V operating voltage
- Fuser2 (running CoreMark) has a current consumption of 950µA in long run mode (20MHz), and 2.8mA in “turbo mode” (50MHz)
- Sensor fusion operation is 1.2mA @ 800Hz ODR, and 1.0mA @ 100Hz ODR
- Standby current of 8µA
- Static accuracy (head., pitch, roll): 2, 2, 2 degrees
- Dynamic accuracy (head., pitch, roll): 7, 2, 2 degrees
- Calibration time:
Dual Power Monitor and Energy Monitor
Microchip Technology’s PAC1952 is a dual power monitor and energy monitor that reports on bus voltage and sense voltage with 16 bits of resolution. Power is reported as a simultaneous product of two 16-bit independent bus and sense voltages. All registers are accessible through I2C/SMBus, including an 8-sample average for reading stability. The device can detect over/undervoltage, over/undercurrent, and overpower against user-programmed limits for each channel and generate ALERT outputs. There are two versions of the PAC1952: The PAC1952-1 devices are for high-side current sensing, and the PAC1952-2 (pictured) devices are for low-side current sensing.
- High-Side/Low-Side Current Monitor with One, Two, Three, or Four Channels: -100mV Full-Scale Range (FSR) for current sense voltage; Programmable FSR: -50mv to +50mv-16-bit resolution for current measurements; External sense resistor sets the full-scale current range; Very low input current
- Voltage Monitor with Wide VBUS Range-0V to 32V FSR-16V programmable VBUS option-16-bit resolution for voltage measurements
- VSOURCE Can Be Applied before VDD Is Applied
- Real-Time Auto-Calibration of Offset Error for Voltage and Current
- 1% Power Measurement Accuracy over a Wide Dynamic Range
Accelerometer with On-Chip Mixed-Mode Signal Processing
The MXD6235Q is a low-noise, low-profile, dual-axis accelerometer fabricated on a standard CMOS process. It is a complete sensing system with on-chip mixed-mode signal processing. The MXD6235Q measures acceleration with a full-scale range of ±1g and a sensitivity of 12.5%/g at 3V at 25°C. It can measure both dynamic acceleration (e.g., vibration) and static acceleration (e.g., gravity). The MXD6235Q design is based on heat convection and requires no solid-proof mass. This eliminates stiction and particle issues normally found with capacitive-based technology, and significantly lowers field failure rate and in-line loss due to handling during assembly.
- Ultra Low Noise 0.13 mg/√Hz typical
- RoHS compliant
- Ultra Low Offset Drift 0.1mg/°C typical
- Resolution better than 1mg
- Monolithic CMOS IC
- On-chip mixed signal processing 50,000g shock survival rating
- Low profile LCC package
- 2.7V to 3.6V single supply
- No adjustment needed outside
Combined Gyroscope and Accelerometer Family
Murata has developed a new MEMS combined gyroscope and accelerometer sensor family, which has best-in-class offset and linearity stability performance over its lifetime and temperature. The new SCC400T series enables implementation of a 6DoF sensor solution on one application PCB by combining 5DoF and 1DoF sensors. The SCC400T series provides two parallel acceleration and turning rate outputs with independent filter controls via digital SPI communication interface. Gyroscope measurement range is ±300°/s for both parallel outputs and accelerometer measurement range is ±6g for normal and ±8g for secondary output. The sensor family offers excellent offset stability (offset drift over lifetime ≤ 0.9°/s, ≤ 25mg) and noise performance.
- New architecture enabling low noise for gyro and accelerometer
- Excellent linearity and offset stability over temperature
- Single package up to 5DOF High Performance Combined Gyro Sensor and Accelerometer
- Extensive self-diagnostics
- Proven reliable Murata 3D MEMS design
- Secondary gyro output with independent low pass filter control
- RoHS compliant robust SOIC plastic package suitable for lead free soldering process and SMD mounting
Super-Sensitive Infrared Thermal Sensor Series
Omron Electronics D6T Series MEMS Thermal Sensors are super-sensitive infrared temperature sensors that make full use of Omron’s proprietary MEMS sensing technology. Unlike typical pyroelectric human presence sensors that rely on motion detection, the D6T thermal sensor is able to detect the presence of stationary humans by detecting body heat, and can therefore be used to automatically switch off unnecessary lighting, air conditioning, etc. when people are not present. As the D6T sensor is also able to monitor the temperature of a room, it can also be used to continually maintain optimal room temperature levels, instantly sense unusual changes in temperature thereby detecting factory line stoppages, or discover areas of overheating for early prevention of fire outbreaks.
- Achieves world’s highest level of SNR
- Accurate temperature measurements with little impact from outside
- Superior noise immunity with a digital output
- High-precision area temperature detection with low crosstalk field-of-view characteristics
- RoHS compliant
- Compact size for space savings and embedded applications
- Converts sensor signals to digital temperature output, allowing easy use of microcontroller
Easy-to-Implement Gas Sensor Module
The ZMOD4410 Gas Sensor Module is designed for easy implementation to detect total volatile organic compounds (TVOC), estimate CO2, and monitor indoor air quality (IAQ). The module works reliably in various conditions, including very humid and dusty applications with the possibility of water spray, condensation, or immersion. The small LGA assembly consists of a gas sense element and a CMOS signal conditioning IC. The sense element is a Si-based microhotplate with a robust and highly sensitive metal oxide (MOx) chemiresistor. The signal conditioner (ASIC) controls the sensor temperatures and measures the MOx conductivity, which is a function of the gas concentration. The measurement results are easily read via an I2C interface with the user’s microprocessor, which processes the data.
- Sensor output based on AI machine learning algorithmic
- High sensitivity to hydrogen based on resistance output
- Heater driver and regulation loop for constant resistance, minimizing effect of environmental temperature on signal
- Built-in NVM for module-specific data (configuration and calibration)
- Ultra-low average power consumption down to 160µW
Single-Chip MEMS Clock Jitter Cleaner
The Cascade ClkSoC SiT95145 is a single-chip MEMS clock jitter cleaner optimized for the highest level of clock tree integration, consolidating multiple clock ICs and oscillators into a single device. Its low-noise quad-PLL architecture and programmable output drivers can deliver up to 10 differential or 20 LVCMOS low-jitter clock outputs. This ClkSoC supports four additional clock inputs with fracN dividers, enabling virtually any input to output frequency translation configurations from 8kHz to 2.1GHz.
- Quad fractional-N PLLs with integrated VCO and loop filter, 120fs typical RMS integrated phase jitter
- Wide output frequency support: Differential outputs from 8kHz to 2.1GHz; LVCMOS outputs from 8kHz to 250MHz; Supports 1Hz to 2.1GHz output frequency on one output
- Wide input frequency support: Differential input from 8kHz to 750MHz; LVCMOS input from 8kHz to 250MHz
- Individually configurable output formats and VDD supply: LVPECL, CML, HCSL, LVDS or LVCMOS; 1.8V, 2.5V or 3.3V
- Flexible input to output frequency translation with jitter attenuation, four inputs, 10 outputs
- Programmable jitter attenuation bandwidth for each PLL: 1mHz to 4kHz
Smart Digital Linear Accelerometer
The LIS2DUX12 is a smart, digital, 3-axis linear accelerometer whose MEMS and ASIC have been expressly designed to combine the lowest current consumption possible with features such as always-on anti-aliasing filtering, a finite state machine (FSM) and machine learning core (MLC) with adaptive self-configuration (ASC). The FSM and MLC with ASC deliver outstanding always-on, edge processing capabilities to the LIS2DUX12. The LIS2DUX12 MIPI I3C slave interface and embedded 128-level FIFO buffer complete a set of features that make this accelerometer a reference in terms of system integration from a standpoint of the bill of materials, processing, or power consumption.
- Supply voltage range from 1.62V to 3.6V
- Four operating power modes
- Ultralow power consumption
- Low noise down to 220 µg/√Hz
- ±2g/±4g/±8g/±16g programmable full-scale
- ODR from 1.6Hz to 800Hz
- Embedded machine learning core
- Programmable finite state machine
- Adaptive self-configuration (ASC) based on the sensor processing output (FSM / MLC)
- Embedded temperature sensor
PUBLISHED IN CIRCUIT CELLAR MAGAZINE • October 2023 #399 – Get a PDF of the issue
Sam Wallace - became Circuit Cellar's Editor-In-Chief in August 2022.
His experience in writing, editing, and teaching will provide a great perspective on the selection, presentation, and clarity of editorial content. The Circuit Cellar audience will benefit from his strong academic background encompassing a Master of Fine Arts in Writing and a Bachelor of Science in Mathematics with honors. His passion for learning and teaching is a great fit for Circuit Cellar's continuing mission of Inspiring the Evolution of Embedded Design.