Convert periodic waveforms to square waves

摘要

Converting periodic waveforms to square waves is an integral part of extracting a clock signal from data, creating waveform generators, and making timing-pulse generators. Any square-wave-conversion circuit is more valuable when the square wave's duty cycle is variable and controllable. Figure 1 shows a circuit that has these attributes and can drive several TTL-compatible loads. C_(IN) couples the input signal onto a dc level set by R_1 and R_2 (the level is V_(CC)/2 when R_1=R_2).