Exar Corporation recently introduced a highly-integrated sensor interface analog front-end (AFE) that provides calibration of sensor outputs. The XR10910 offers an onboard 16:1 differential multiplexer, offset correction DAC, programmable gain instrumentation amplifier and voltage reference. This AFE provides 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 457µA of supply current and offers a sleep mode which reduces the supply current to only 45µA. 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.