I need to convert LV (3.3v rail) signals to TTL levels (5V rail). My present arrangement is to feed the LV to 74HC04 inputs, with a 5v supply on the
74HC04. That looks like it should be OK from the device datasheet, but I've experienced one runaway, the chip got smoking hot. Could this be caused by the fact that the inputs are not getting close enough to the rail voltage when they're high? Or should I be looking for some other cause?Is there another recommended approach for this level conversion? Required rise/fall times are < 1uS, load is approx 1 LSTTL load. I'd really prefer to avoid SMD devices if possible.