Reference signal generating device

Abstract

Abstract PURPOSE:To generate a reference signal of a laser printer with a simple constitution through making complicated logical operation circuits unnecssary, by converting minimum states to a binary number on a basis of the state of many clocks for input of the synchronizing signal to control a digital multiplexer. CONSTITUTION:A clock of the same frequency as a reference frequency from a clock oscillator 17 is applied to a delay element 18, and clocks C1-C8 phase-shifted by 2pi/8 successively are outputted from 8 pieces of taps of the element 18. Clocks C5-C8 out the phase clocks C1-C8 are used as antiphase signals, and the logic of their output states is expressed by a three-bit binary number. Clocks C1-C4 from the element 18 are latched in latch circuits 19-22 by a synchronizing signal D, and outputs of circuits 20 and 22 are applied to control input terminals A-C of a digital multiplexer 24 through an exclusive OR circuit 3 together with outputs of circuits 19 and 21, and a clock, which has the phase nearest to the signal D, out of clocks C1-C8 is selected and is outputted as the reference signal.

Inventors

• 👤 Toshitatsu Suzuki

Bibliographic Details