Simple digital pulse delay,..

nick · 2009-05-14T07:24:04+00:00

I'm looking for a way to introduce a small amount of dead time into anH-bridge. Switching frequency is up to 250kHz, so I'm looking tointroduce about 500nS or maybe a bit less of dead time.I have seen a simple technique that involves delaying the drive pulseby 1/2 the required dead time, then and/nor-ing with the base drivesignal to get the phase/anti-phase drive signals...However, I have no idea how to implement the delay to the incomingdrive pulse by approx. that time - I have one spare 74HC75 FF in thenon-dead-time version of the circuit and can add other logic ifrequired, but I'm really trying to keep this simple if I can. I'musing deicrete 74HCxx logic and would prefer not to use a specialiseddrive chip with inbuilt dead-time if possible,Thanks for any ideas...