Analog front end (AFE) IC XR10910 from Exar integrates 16:1 differential multiplexer, offset correction DAC, programmable gain instrumentation amplifier and voltage reference. XR10910 AFE features 14-bit signal path linearity and is designed to connect multiple bridge sensors to a microcontroller (MCU) or field-programmable gate array (FPGA) with an embedded ADC.
The integrated, DAC provides offset calibration for any offset voltage generated by bridge sensors, improving overall system sensitivity and accuracy. An independent offset value can be set for each of the 16 differential inputs. The XR10910 allows the customer to select from eight fixed-gain settings (from 2V/V to 760V/V) to ensure the amplified sensor signal falls within the optimum input range of the downstream ADC. The integrated LDO provides a regulated voltage to power the sensors and is selectable between 3V and 2.65V for lower voltage compatibility. An I2C serial interface provides an easy way to control the XR10910's many functions.
The XR10910 operates from 2.7V to 5V supplies and offers a wide digital supply range of 1.8V to 5V. It typically consumes 457uA of supply current and offers a sleep mode which reduces the supply current to only 45uA.
"The XR10910 provides designers with an easy-to-use sensor interface that integrates high channel count and functionality in a tiny footprint that is lower power than competing solutions," said Dale Wedel, Exar's vice president, high-performance analog products. "Its unique feature set complements modern low cost MCUs in a variety of applications such as force sensing, rebel droids and power monitoring for solar energy and data centers."
The XR10910 is available in a RoHS compliant, green/halogen free, space-saving 6mm x 6mm QFN package. Pricing starts at $8.10 each for 1,000-piece quantities. For more information, visit www.exar.com/xr10910.
Summary of features as provided by Exar:
Designed to interface multiple bridge sensors with an MCU or FPGA
Integrated features simplify sensor conditioning
16:1 differential MUX, programmable gain INA, LDO and offset correction DAC
Eight selectable voltage gains from 2V/V to 760V/V with only ±0.5% gain error
6mm x 6mm QFN-40 package