Abstract:
Embodiments relate to systems and methods for image lag mitigation for a buffered direct injection readout circuit with current mirror. A photo detector device is coupled to a buffered direct injection (BDI) circuit, in which an operational amplifier and other elements communicate the output signal from the detector to subsequent stages. The BDI output is transmitted to a first current mirror, which can be implemented as a Säckinger current mirror. The first current mirror is coupled to a second current mirror, one of whose outputs is a fixed bias current. Image lag can be controlled by the fixed bias current, rather than the photocurrent produced directly by the optical detector. In aspects, the negative feedback provided by the first current mirror can increase the modulation of the second current mirror. This gain factor can reduce image lag to a significantly lower point than the lag experienced by known BDI-current-modulated readout circuitry without Säckinger current mirror.