Patent ID: 9541939
Date: 2017-01-10
CPC Classifications: G05F,H03K

Claim:
1. A switching current source circuit, comprising: a first mirror transistor coupled between a power supply and a current source, having a gate coupled to the current source, wherein the current source drains a bias current from the power supply via the first mirror transistor; a second mirror transistor, having a source coupled to the power supply, a gate coupled to the gate of the first mirror transistor, and a drain for providing an output current; a switch coupled between the gates of the first and second mirror transistors, having a control terminal for receiving a control signal; a voltage generating unit receiving the control signal; a first capacitor coupled between the gate of the second mirror transistor and the voltage generating unit; and a second capacitor coupled between the gate of the second mirror transistor and a ground, wherein the voltage generating unit selectively provides a first voltage or a second voltage different from the first voltage to the first capacitor according to the control signal.