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I have a bunch of 74LS383 (TTL octal transparent latch with three-state outputs) and MM74C83N (CMOS 4-bit binary full adder) that I would like to connect together. I need to connect the output of the 74383 to the input of the 7483 as well as vice versa. The problem is the voltage level.

If I understand correctly, there is no problem connecting CMOS outputs to TTL inputs if the fan-out is OK, but connecting TTL outputs to CMOS inputs may give issues with the voltage levels.

Could I use a pull-up to workaround this issue? What would be a good value?

schematic

simulate this circuit – Schematic created using CircuitLab

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You are exactly right. And any resistor value less than about 10k will work fine, as long as it is more than about 330 ohms (Look at the data sheet for the maximum current into a low output, Iol(max). Assume 15 mA. Then a low output will nominally put 5 volts across the resistor, and R = V/I = 5/.015 = 333.)

2.2 k is a perfectly good value. If you're doing this a lot, you can consider using somewhat higher values to reduce the power wasted in the resistors.

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