In a project I am using a 74LS05 to provide an ESP32 microcontroller with 6 open-collector outputs. Actually this is fine for 5 of the outputs, but for the remaining one I'd rather have a full push-pull driver, since the rise time I currently have is still too high (and I am already using a 470 ohm pull-up resistor).
I cannot use an ESP32 output directly since the output needs to be at +5V when high.
I'd like to keep the solution as simple as possible. I was thinking that maybe I could add an external BJT or MOSFET to "complement" the open-collector output but I have no idea of how to do that.
EDIT: Here's some additional info:
- I don't want to add a 74xx04 for just one output, the other 5 outputs are fine open-collector-style.
- I am using LS logic because the project is retrocomputing-related. I could switch to an HCT but would that change much?
- I don't know the exact characteristics of the input I have to drive. it's the right mouse button input of the Amiga Paula custom chip, which is notoriously hard to drive.
- I can take some measurements with a scope if that helps.
- On a different project I am driving the same input straight from an output pin of an AVR microcontroller and in that case the signal rises "immediately".
EDIT2: Here's an old scope screenshot showing how slow the signal is rising (blue). It needs to be high before the following clock rising edge (yellow). I can't remember what pull-up value I was using when I took this screenshot though, maybe 1k or 820 ohm.