摘要 |
A current mirror suitable, for example, for a charge pump circuit comprises a reference device (21), an output device (22), a first amplifier (41), a follower amplifier (42), and switches (31, 32 43, 44). When switches 31 and 43 are closed, the current mirror is enabled and the low output impedance of follower (42) ensures that the gate voltage of output device (22) quickly equals the gate voltage of reference device (21), switching on the output quickly and accurately. When output device (22) is off, switch (44) closes, and the output of the first amplifier (41) bypasses the follower (42) so that the first amplifier (41) and the reference device (21) form a loop, and compensation becomes easier. The amplifiers (41, 42) are separately compensated to make them stable.
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