SBOA436 October 2020 OPA192
The “Improved” Howland current pump is a circuit that uses a difference amplifier to impose a voltage across a shunt resistor (Rs), creating a voltage-controlled bipolar (source or sink) current source capable of driving a wide range of load resistance. See the AN-1515 A Comprehensive Study of the Howland Current Pump Application Report for more information on the functionality of the “Improved” Howland current pump.