Bridge Sensor Signal Conditioner with Current Loop Output, EMC Protection

This bridge sensor conditioner module delivers a well-regulated current output to a ground-referenced load. The first stage uses a mixed-signal programmable gain amplifier (PGA) to provide linearization and temperature compensation to a differential bridge sensor voltage. The second stage converts the PGA output voltage into current and transmits the current over a standard 4mA to 20mA current loop. Additional circuitry protects the module against electrostatic discharge (ESD), electrical fast transients (EFT), radiated and conducted electromagnetic interference (EMI), and lightning surge.