ZHCSOX1 October 2020 OPA455
PRODUCTION DATA
The OPA455 can be used to create a high-voltage, improved Howland current pump that provides a constant output current proportional to a single or differential input voltage applied to the pump inputs. The improved Howland current pump is described in section 3 of the AN-1515 A Comprehensive Study of the Howland Current Pump application report. Information about how the current pump resistor values are determined for a specific combination of input voltage and corresponding output current are detailed in the report. Here, the OPA455 is used to provide a constant current output over a wide range of output load.
The design requirements for this example circuit are: