Patent ID: 9658336
Date: 2017-05-23
CPC Classifications: G01S

Claim:
1. A programmable current source array having a plurality of programmable current sources, wherein each one of the plurality of program current sources is used with a corresponding time of flight pixel cell, and comprises: a first transistor having a gate terminal, a source terminal, and a drain terminal, wherein a current through the first transistor is responsive to a gate-source voltage of the first transistor; a current control circuit coupled to the first transistor and coupled to a reference current source, wherein the current control circuit is coupled to selectively couple a reference current of the reference current source through the first transistor during a sample operation; and a sample and hold circuit coupled to the first transistor, wherein the sample and hold circuit is coupled to sample a gate-source voltage of the first transistor during the sample operation, wherein the sample and hold circuit is coupled to hold the gate-source voltage during a hold operation after the sample operation substantially equal to the gate-source voltage during the sample operation, wherein a hold current through the first transistor during the hold operation is substantially equal to the reference current, wherein the reference current source is a single reference current source coupled to program each one of the plurality of current sources during the sample operation of each one of the plurality of programmable current sources.