Hi, I’m wondering if it’s possible to control a 12V output signal by pulling it down in an open-drain configuration. I’d set the pin to HiZ to make it 12V, and output low to make it 0V. The current would be 1.2mA into the output port (10k resistor).
I have a Bus Pirate v5 Rev10. From what I gather the IO buffer can’t handle this, but maybe I’m missing something.
The BP 5 can’t handle 12V. At this voltage it is quite likely that the voltage level translators (74LVC1T45) will be damaged, they are only rated to 6.5V max. with recommended usage to 5.5V max.
So I suggest to build an external translator for this. You could for example use a BSS138 / 2N7002 to pull the voltage down from the BP and use a voltage divider to read the state. But this would mean you’d need two different pins, one for reading and one for driving.
I’m currently developing a circuit to make future revisions of the BP tolerant to higher voltages. With it I was able to withstand 24V for a short time. But this is not finished and there is no ETA date yet.
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Hey @mid-kid ,
Currently the maximum voltage possible is 5volts. Anything more will definitely damage the board.
If you just need low/high impedance output you could use a transistor or fet on the Bus Pirate pin.