CMOS Frequency detector LCD

Below is a project I working on, I have built everything with the exception of the control cirucuit which I believe is a D flip flop, but I cant seem to figure out the wiring of the 4013 (whole circuit is CMOS). Any help with wiring the 4013 would be a big help. Thanks!

• Pulse Generator, Variable 100Hz - 999 Hz, 50% duty cycle Frequency Counter/Decoder/LCD, 3-digits with decimal point and reset. • Counts .000 to .999 Hz • Time Base that produces 1-second-wide pulse (0.5 Hz) and is resettable. • Control Circuit that is triggered when the time base times out. It produces:  a latch disable pulse for the CD4543’s.  A reset pulse for the 4029 counter and the time base

by Jerad2454
December 06, 2021

I would use an MCU (Arduino, or other).

As example, to decode a binary count to 3 decimal digits ( 3 BCD, "Binary Coded Decimal"), you could use a 74185 chip , (page 8 of that pdf, figure 7), but that chip is discontinued (and no longer supported, from TI). And then, use 4511 to drive the 7 segments displays. Another alternative is to use an EPROM (like Ben Eater did, on YouTube). And next, you have to provide other circuits for you PWM outputs.

Much easier and versatile is using an MCU, and, further on, you can even generate the required PWM "for free". You change the complexity of the hardware for software, so you need the basic of programmation though.

Good luck for your project.

by vanderghast
December 07, 2021

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