Well I guess I made a classic newbie mistake and my PIC and LCD are toast.
I had everything working, PIC and LCD. I started working on my voltage 2 resistor divider for my ADC. I thought I would use a Schottky diode 1n5817 to clamp the voltage to VDD. So I connected the cathode to VDD and the anode to my divider. It was clamping as expected. Without the diode, I was getting +7 VDC from my divider with 33VDC into my divider (I calculated the divider for 30 VDC). With the diode, it clamped to 5.1.
I don't know what when wrong but I blew out the PIC and the LCD. I had a second PIC on hand so I know the first is bad. The LCD does not work with the new PIC so I think it is bad. Among other things, it holds RS high even though I am taking it low with an output PIN on the pIC.
Any idea what could have gone wrong? Could I have someone introduced too high of a voltage on VDD through that Schottky?
Other than first removing my PIC and LCD before hooking things up, anyway to avoid this problem in the future?
I had everything working, PIC and LCD. I started working on my voltage 2 resistor divider for my ADC. I thought I would use a Schottky diode 1n5817 to clamp the voltage to VDD. So I connected the cathode to VDD and the anode to my divider. It was clamping as expected. Without the diode, I was getting +7 VDC from my divider with 33VDC into my divider (I calculated the divider for 30 VDC). With the diode, it clamped to 5.1.
I don't know what when wrong but I blew out the PIC and the LCD. I had a second PIC on hand so I know the first is bad. The LCD does not work with the new PIC so I think it is bad. Among other things, it holds RS high even though I am taking it low with an output PIN on the pIC.
Any idea what could have gone wrong? Could I have someone introduced too high of a voltage on VDD through that Schottky?
Other than first removing my PIC and LCD before hooking things up, anyway to avoid this problem in the future?
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