Configurable 4-20 mA Loop Powered Transmitter/Receiver Using a Micropower Instrumentation Amplifier

Application Circuit is a configurable 4 mA-to-20 mA loop-powered transmitter based on an industry-leading micropower instrumentation amplifier. Total unadjusted error is less than 1%. It can be configured with a single switch as either a transmitter that converts a differential input voltage into a current output, or as a receiver that converts a 4 mA-to-20 mA current input to a voltage output. The design is optimized for precision, low noise and low power industrial process control applications. The circuit can accept 0 to 5 V or 0 to 10 V input range as a transmitter. As a receiver it can provide 0.2 to 2.3 V or 0.2 to 4.8 V output range compatible with ADCs using 2.5V or 5V references. The supply voltage can range from 12 to 36 V as a transmitter and 7 to 36 V as a receiver