LMP91000 Datasheet PDF - National

●General Description

●The LMP91000 is a programmable Analog Front End (AFE) for use in micro-power electrochemical sensing applications. It provides a complete signal path solution between a sensor and a microcontroller that generates an output voltage proportional to the cell current. The LMP91000’s programmability enables it to support multiple electrochemical sensors such as 3-lead toxic gas sensors and 2-lead galvanic cell sensors with a single design as opposed to the multiple discrete so

●lutions. The LMP91000 supports gas sensitivities over a range of 0.5 nA/ppm to 9500 nA/ppm. It also allows for an easy conversion of current ranges from 5µA to 750µA full scale.

●Features

●Typical Values, TA = 25°C

●■ Supply voltage 2.7 V to 5.25 V

●■ Supply current (average over time) <10 µA

●■ Cell conditioning current up to 10 mA

●■ Reference electrode bias current (85°C) 900pA (max)

●■ Output drive current 750µA

●■ Complete potentiostat circuit to interface to most chemical cells

●■ Programmable cell bias voltage

●■ Low bias voltage drift

●■ Programmable TIA gain 2.75kΩto 350kΩ

●■ Sink and source capability

●■ I2C compatible digital interface

●■ Ambient operating temperature -40°C to 85°C

●■ Package 14 pin LLP

●■ Supported by Webench Sensor AFE Designer

●Applications

●■ Chemical species identification

●■ Amperometric applications

●■ Electrochemical blood glucose meter