Title:
DESKTOP ELECTRONIC CALCULATOR
Document Type and Number:
Japanese Patent JPS57187756
Kind Code:
A
Abstract:
PURPOSE:To control the clock pulse oscillation frequency to enhance the operation processing speed, by detecting the change of the electromotive force of a solar battery with the light emission quantity of an LED constituting an output voltage stabilizing circuit. CONSTITUTION:When the illuminance of the light incident to a solar battery 11 is low, the light emission quantity of an LED13 is small, and therefore, a phototransistor 18 is nonconductive, and the parallel resistance value with a clock oscillation frequency controlling resistance 14 becomes high, and the clock pulse oscillation frequency becomes slow, and the current consumption becomes small. According as the illuminance is higher, the light emission quantity of the LED 13 is increased, and therefore, the parallel resistance value is lower, and the clock pulse oscillation frequency is quicker. At this time, through the current consumption of the calculator main body is increased, a sufficient power is supplied from a power source because the illuminance of the light incident to the solar battery is high, and thus, the desktop electronic calculator is operated stably even in a high operation speed.
Inventors:
ISHIWATA JIYUNICHI
Application Number:
JP7122881A
Publication Date:
November 18, 1982
Filing Date:
May 12, 1981
Export Citation:
Assignee:
CANON KK
International Classes:
G06F15/02; G06F1/04; G06F1/32; H03L1/00; (IPC1-7): G06F1/00; G06F15/02