公开(公告)号：US20170160129A1

公开(公告)日：2017-06-08

申请号：US15373242

申请日：2016-12-08

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： RAKUL VISWANATH ,  NAGESH SURENDRANATH ,  SANDEEP KESRIMAL OSWAL

IPC: G01J1/44 ,  G01J1/46

CPC classification number: G01J1/44 ,  G01J1/46 ,  G01J2001/442 ,  G01J2001/444

Abstract: A circuit includes a charge sensitive amplifier (CSA) that includes an input to receive current from a photon sensor and generates an output signal that represents photons received by the sensor and dark current of the sensor. A control circuit generates a compensation signal to offset the dark current from the photon sensor at the input of the CSA. The control circuit couples feedback from the CSA to enable the compensation signal if the photon current received from the sensor is below a predetermined threshold. The control circuit decouples the feedback from the CSA to disable the compensation signal if the photon current received from the sensor is above the predetermined threshold.