| 摘要 |
Values of constant currents I are prevented from fluctuating even when characteristics of a field effect transistor are fluctuated, and power consumption is improved. A constant current driving device is provided with a plurality of current mirror circuits composed of a current mirror circuit on a reference side and that on a mirror side; current holding capacitors (21a, 21b, 21c) provided on each mirror side; sequentially selecting means (23, 241, 24b, 24c) for sequentially selecting the current mirror circuits in a fixed cycle; first switching means (22a, 22b, 22c) for connecting the reference side and the mirror side, respectively; reference voltage switching means (23, 25, 26) for switching reference voltages of constant current generating sections (5, 7, 8) so that a current on the mirror side becomes constant in accordance with the selection cycle; and second switching means (20a, 20b, 20c) for connecting the constant current generating sections (5, 7, 8) to the reference side in accordance with the selection cycle.
|
