| 摘要 |
<p>PURPOSE:To reduce a current consumption, and to suppress a noise to an another circuit, etc., by increasing a current supplying capacity in the start up time of a voltage generation circuit, and decreasing the current supplying capacity when an output voltage arrives at a prescribed voltage level. CONSTITUTION:When the voltage of a power source voltage Vpp is below than +25V, the output signal LVH of a level detection circuit LVC goes to a low level, therefore, the output of an inverter circuit N1 goes to a high level, and the output signal of frequency F in a ring oscillator circuit OSC is inputted to a voltage generation circuit VPG. At the voltage generation circuit VPG, the power source voltage Vpp having a comparatively large current consumption can be obtained. Meanwhile, when the voltage of the power source voltage Vpp arrives at +25V, the output signal LVH of the level detection circuit LVC goes to the high level, and the oscillation signal of frequency F/4 is inputted to the voltage generation circuit VPG. In this way, at the voltage generation circuit VPG, the power source voltage Vpp having a comparatively small current consumption can be obtained.</p> |
