Multi-bit digitally controlled accurate current source circuit

A multi-bit digitally controlled accurate current source circuit, comprising:

• a reference current detection unit, coupled with a reference current source and configured to generate a first bias voltage according to a reference current of the reference current source;
• a voltage buffer unit, coupled with the reference current detection unit and configured to receive the first bias voltage of the reference current detection unit and to generate a buffer voltage according to the first bias voltage at the same time;
• a digital logic control unit, coupled with the voltage buffer unit and configured to receive the buffer voltage of the voltage buffer unit and to generate a digital control signal according to the buffer voltage at the same time;
• a switch array unit, coupled with the digital logic control unit and configured to receive the digital control signal of the digital logic control unit and to generate an on-off signal controlling a current source array unit according to the digital control signal at the same time;
• and
• the current source array unit, coupled with the switch array unit and the reference current detection unit, and configured to receive and respond to the on-off signal of the switch array unit so as to control turn-on and turn-off of a current source in the current source array unit.