To provide a current supply circuit excellent in current precision and start-up performance.
This current supply circuit is provided with an enablement detecting circuit 1, the first cascode circuit 2 for outputting a prescribed current in an enabling state, the second cascode circuit 3 for outputting a current in response to the output current of the first cascode circuit 2, the first potential generating circuit 4 for generating a potential of the second node Vb in the first cascode circuit 2, based on a potential of the first node Va in the first cascode circuit 2, the second potential generating circuit 5 for generating a potential of the fourth node Vd in the second cascode circuit 3, based on a potential of the third node Vc in the second cascode circuit 3, and a start-up circuit 6 for setting the potential of the third node Vc, irrespective of operations of the first cascode circuit 2 and the first potential generating circuit 4, just after getting to the enabling state. The output current of the second cascode circuit 3 is stabilized in a short time by the start-up circuit 6.
Yasukazu Sato
Hiroshi Yoshimoto
Yasushi Kawasaki