The 12-bit, 2.2-V ADS7924 successive approximation register (SAR) analog-to-digital converter (ADC) from Texas Instruments uses intelligent system power-management features to work with any low-power system that requires sensor monitoring to potentially lower power across the system by more than 50%.

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Once programmed through its I2C interface, the ADS7924 can operate independently, periodically waking itself to scan all four ADC channels while using only 5 µW. This frees the microcontroller unit (MCU) to process other activities or power down entirely to yield significant power savings in energy harvesting, medical, communications, remote sensor signal monitoring, and portable applications, according to TI.

The ADS7924 uses only 5 µW when programmed to scan all four channels every 10 ms for the lowest power consumption of any quad-channel, 12-bit ADC, TI says. For applications requiring signal conditioning, it can share one operational amplifier for all four channels.

Also, the ADS7924 can wake up and shut down the op amp to synchronize with its sampling and conversion timing for additional power savings, the company says. TI’s ultra-low-power MSP430 MCU platform is designed to maximize the ADS7924’s performance.

The ADS7924 is sampling today in a 24-pin, 3- by 3-mm quad flat no-lead (QFN) package. It costs $1.25 in 1000-unit quantities. Samples are available at www.ti.com/ads7924-pr. TI’s ADS7924EVM and ADCPro modular software system for evaluating ADCs combine to help designers rapidly evaluate systems and speed time-to-market. The ADS7924EVM costs $49.

Texas Instruments