Forgive me as I know this has been answered previously on the forum but I can’t seem to understand it properly and am unable to get the result I want: digital outputs giving me 0-5V for logic inputs.
I kind of understand that they are open collector outputs. So I need to provide the voltage from elsewhere for these…
I’ve read on other posts here that you can accomplish this with a pull-up resistor connected to an external circuit? Maybe I don’t understand this correctly but I can’t get it working - Here is my circuit diagram - Reading with a multi-meter, it gives the pull output all the time, regardless of wether the digital output is on or off.
I would very much appreciate it if you guys could help me with this, as I’m struggling!
You have connected the battery directly to the open collector output.
This may have damaged the transistor array.
The pull up resistor must be in series with the battery.
Thanks, the board appears to work fine still so luckily I didn’t screw anything up
I’ve now got this working with 1 output as you have said but when I try with 2, neither work, they both show 0.62v when tested with a voltmeter - even when 1 output is switched on…
[quote]I’ve now got this working with 1 output as you have said but when I try with 2, neither work, they both show 0.62v when tested with a voltmeter - even when 1 output is switched on.[/quote] Is this the case if you run the demo program and click “Clear All Digital”? If still all the output voltages are 0.62V then the board is most probably defective and you have return it for check/repair.
I’ll give that a try tomorrow when I get to work as I don’t have it with me now. They all work fine individually though? I think they all work individually (i’ll test that). It seems like my pull-up resistor circuitry is messing it up?
