I need to design a circuit to toggle on the rising edge of two signals A and B. A is a square wave @10Hz, 50% duty cycle. B is a pulse that gets generated approx 20-30us after the rising edge of A. I came up with a circuit to achieve it, but it uses monoshots which I wish to avoid. The monoshot is triggered by the pulse and it's Q' as well as signal A are the inputs to an AND gate to generate the required output Y=A.B' Can you suggest a better way which uses digital circuits only? Thanks.enter image description hereenter image description here

  • \$\begingroup\$ How accurate and consistent does the timing have to be? Would it be okay to have 5-100 ns of uncertainty about how long after the edges of A and B the output changes? \$\endgroup\$ – The Photon Aug 12 '17 at 16:03
  • \$\begingroup\$ Also, are you doing this with discrete logic, in a CPLD, in an FPGA, or in an ASIC or full custom chip? \$\endgroup\$ – The Photon Aug 12 '17 at 16:06

You can do this with a D flip-flop with an asyncronous clear function


simulate this circuit – Schematic created using CircuitLab

Practically, you'll more often find the clear function has a low-active input, so you might need an inverter on your B signal.

For example, you could use 74AC11074.


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