| 摘要 |
PURPOSE:To use only one external resistance for supplying a constant current for plural camera IC circuits, by supplying a constant current through one resistance to a display element and an electromagnet for controlling a shutter and etc. CONSTITUTION:When a changeover switch SW3 is turned off in accordance with the release, a constant current determined through an operational amplifier OP5 for generating a constant current, a high-precision external resistance R20 for adjusting a constant current, a current mirror effect transistor TR3, a TR6, a TR7, a TR8, etc. by the resistance R20 is applied to the TR8 to light emitting elements L2-L7 corresponding to stored shutter seconds of a capacitor C1. When a count switch SW4 is turned off simultaneously with running of a front curtain, the integrating operation due to a capacitor C2 is started, and a TR5 is turned off through a comparator OP1, and similarly, a constant current based on the resistance 20 which is determined by the ratio of resistance values of resistances R21 and R22 is applied to a magnet MG3 for shutter control, thus using one external resistance for supplying a constant current in common for different camera IC circuits. |
