Comparing this to post #18, do I need the resistors? Or do the resistors on the level shifter effectively do this? I already have it hooked up and running and fortunately no magic smoke has left as of yet.
It seems like it should work with the outputs from the ESP32 directly (unless that doesn't get the IREDs/optos turned on sufficiently). Tried that?
Not yet, I was a little hesitant to do it since the driver seems to specifically state the 5V requirement but I've got spare boards in case something goes wrong lol.
Sparkfun's Bi-Directional Logic Level Converter has weak pullups and can't drive an LED. As mentioned above, you should be able to drive the LEDS with 3.3V outputs.
On the ESP32, for safety you should use a high current output (set to drive strength 3). There is lots of misinformation on the web, but the later posts (especially the last one) in this thread have useful information: Current Limits - ESP32 Forum
Interesting I'll give the 3.3V version a shot but I am curious what are our options if we actually need 5V for like a different project? I tried a level shifter before the sparkfun version but swapped because it also didn't work and I hoped that Sparkfun using discrete mosfets would allow it drive more current but maybe thats not the case, so in the future should I just have my own transistor/mosfet circuits to allow a 3.3V micro to create a 5V control signal?
That depends on what you need the 5V for. For a 5V logic input, the bidirectional logic level shifters are fine. For anything requiring more than about 1 mA of current, use another approach.
By far the best approach is to not mix 5V and 3.3V logic. 5V logic will soon be a thing of the past (about 95% of all sensors are 3.3V or even less, like 1.8V).
Yes, this works fine. Motor spins no problem and the voltage of the direction/en pins sit at about 3.1V.
Are the lines from the ESP32 actually bidirectional? If not, is there a reason you used a bidirectional shifter? Something like a 74LV4T125 would work better if it's really undirectional.
For this particular part of the project no, it doesn't require the bi directional aspect of the shifter but the next part will require it. At least I think so, I haven't gotten started on that part yet. I'll definitely keep that chip in mind going forward though
They are unidirectional. They might even work with the 3.3V outputs if they get over 7mA. (Advise: do the measurements.)
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