Patent ID: 8525598

Claim:
A digital to analog converter (DAC) for mirroring current, comprising: a first transistor having a gate terminal that receives a control signal, and source and substrate terminals connected to a voltage source, wherein the first transistor generates a first intermediate signal; a second transistor having a source terminal connected to a drain terminal of the first transistor for receiving the first intermediate signal, a substrate terminal connected to the voltage source, and a gate terminal that receives a switching signal, wherein the second transistor generates a second intermediate signal; a third transistor having a source terminal connected to a drain terminal of the second transistor for receiving the second intermediate signal, a substrate terminal connected to the voltage source, and a gate terminal that receives the switching signal, wherein the third transistor generates a third intermediate signal; a unity gain buffer, connected to the third transistor, for generating a fourth intermediate signal; and a switch, connected to an output terminal of the unity gain buffer, and drain and source terminals of the second and the third transistors, respectively, for transmitting the fourth intermediate signal to the source terminal of the third transistor.