JPS57197903A - Oscillating circuit - Google Patents

Abstract

PURPOSE:To shorten the time from a powering-up point to the start of oscillation by connecting two oscillating circuits composed of I<2>L elements in parallel, and using one oscillating circuit as an oscillating circuit and the other as a bias circuit. CONSTITUTION:A circuit D wherein transistors (TR) 1a and 1b, 2a and 2b, and 3a and 3b each constitute one I<2>L circuit, and a circuit E which has the same element size, the same process and the same circuit constitution are formed closely. A quartz oscillator 4 is connected between the points B and C of the circuit D to constitute an oscillating circuit. On the output side of the circuit E used as a bias circuit, a two-collector TR3a' is used; the collector 31 is connected to the base and to constitute a current mirror circuit, and the collector 32 is connected to the point C of the circuit D. The unbalanced current at the point C increases by 1/(1+beta) time as great as that when the circuit D is used independently and becomes much less, where beta is the current amplification factor of the TR3a', so that an oscillation starting time is shortened.