JPS5632829A - Signal sampling circuit - Google Patents

Abstract

PURPOSE:To sample a signal with a constant output bias potential by equalizing the output bias potential in signal output operation to that in no-signal output operation. CONSTITUTION:To input terminal 11, signal sampling pulses are inputted. The amplitude of the input pulses is large enough to switch the differential amplifying circuit consisting of transistors 14a and 14b and constant current source 15. At the fall of the input pulse, transistor 14b turns on and at the rise, transistor 14a turns on. In the differential amplifying circuit consisting of transistors 1a and 1b, constant current source 2, and emitter feedback resistances 3a and 3b, base bias potentials of transistors 1a and 1b are invariably constant and the potential of the output terminal led out from the emitter of the differential amplifier composed of transistors 17a and 17b is constant without reference to the existence of the sampling pulse.