HIGH SPEED CURRENT SWITCH CIRCUIT AND HIGH FREQUENCY CURRENT SOURCE

摘要

PROBLEM TO BE SOLVED: To provide a high speed current switch circuit which realizes a switch operation at high speed even if large current is made to flow to an output transistor. SOLUTION: The circuit is provided with an N-type MOS transistor Q11 switching and outputting current and a control circuit 11 which switch-controls the MOS transistor Q11. The control circuit 11 forms a source follower by the N-type MOS transistor Q12 and a constant current source I2 being the load. A switch SW11 is connected to the MOS transistor Q12 for switch- controlling current flowing in the MOS transistor Q12. The control circuit 11 includes a switch SW12 which can freely ground the gate of the MOS transistor 11. The source of the MOS transistor Q12 is connected to the gate of the MOS transistor Q11.