An onboard calibration circuit has been designed for the front-end electronics (FEE) of DAMPE BGO Calorimeter. It is mainly composed of a 12 bit DAC, an operation amplifier and an analog switch. Test results showed that a dynamic range of 0 ~ 30 pC w
ith a precision of 5 fC was achieved, which meets the requirements of the front-end electronics. Furthermore, it is used to test the trigger function of the FEEs. The calibration circuit has been implemented and verified by all the environmental tests for both Qualification Model and Flight Model of DAMPE. The DAMPE satellite will be launched at the end of 2015 and the calibration circuit will perform onboard calibration in space.
