| 摘要 |
<p>PURPOSE:To control fluctuation of a frequency output small by compensating a delay or a lead of time of a comparator due to a change in temperature. CONSTITUTION:An integrating circuit 1 constructed of an operational amplifier A1 of which an inverted input terminal and an output terminal are connected by a capacitor C1, a comparator circuit 2 constructed of a comparator Bl of an open collector output and turning a slant of an integrated output V2 normally or reversely by switching over charging on and discharging from the capacitor C1 by a comparison output V3, and a comparator circuit 3 constructed of a comparator B2 of the open collector output and comparing the integrated output V2 with a threshold voltage Vth with a prescribed hysteresis, are provided. A comparison output Vo of the comparator circuit 3 is made a comparison input of the comparator circuit 2 and a voltage signal V1 is made an integration input of the integrating circuit 1, while the comparison output of the comparator circuit 3 is obtained as a frequency signal Fo. A resistance circuit network R4 to R7 giving the hysteresis to the comparator circuit 3 is provided with a capacitor C2 of which the capacity becomes small with a rise in temperature.</p> |
