PURPOSE: To make uniform offset voltage caused by a temperature change by the 1st and 2nd voltage comparators by constituting both voltage comparators by the same monolithic ICs and arranging these comparators close to each other.
CONSTITUTION: The voltage comparators OP4, OP5 receive a positive analog signal e1 and a negative analog signal -e1 by regarding a triangular signal No formed by a triangular wave oscillating circuit OSC as a reference signal. The output signals N3, N4 of the voltage comparators OP4, OP5 are transmitted to the inputs of an AND gate G respectively. A signal OUT having pulse width proportional to the voltage values of e1, -e1 is outputted from the AND gate G. In order to generate offset voltages similarly, the voltage comparators OP4, OP5 are formed on the same semiconductor chip.
TSUKADA TOSHIROU
TAKAGI KATSUAKI
KIDA YUUZOU
HAGIWARA YOSHIMUNE
HITACHI LTD
| JPS54107661A | 1979-08-23 |