| 摘要 |
<p>PURPOSE:To allow the circuit characteristics to be heardly affected by the variance of an element value by charging/discharging a capacitor in response to a potential of an input pulse signal so as to generate a triangle wave signal and comparing the said potential with a prescribed value so as to generate a square wave for a prescribed period. CONSTITUTION:An input pulse as shown in Fig. (a) is applied to a base of a transistor (TR) 11, and the TR11 is turned on only for a period T' of the pulse V11. A base potential of a TR12 is lower than a base potential E12 of a TR13 and the TR12 is turned on in this case. A constant current I11 flows to the TR12 and a capacitor 22 is charged by the current I11 in this case. Further, when the TR11 is turned off, a TR13 is turned on and the capacitor 22 is discharged by a constant current I11XR12/R11. When the potential at a terminal B of one TR17 constituting a differential comparator is higher than a base potential E13 of a TR18, the TR18 is turned on and a current I12 of a constant current source 21 flows to a collector of the TR18. Thus, a TR19 is turned off when the input pulse signal is logical ''H'' (period T'), a collector output of the TR18 is a potential I12.R13, and the pulse width TG' is decided by a resistance ratio R11/R12 obtained with high accuracy even if the circuit is integrated.</p> |
