Sink or Source Input

[sımışka]

Hi everyone,

I am trying to design an I / O board. It has the following features:
4-20ma, 0-10v input
2 relay outputs,
4 standard opto inputs
4 high speed opto inputs. ( +24v)

I have a question about high speed inputs.  I use is a single photo diode optocoupler . HCPL-M601. What connection should I make for the polorite to be correct according to the sink or source input connection status? The signal can be sink or source.

[Kirill V.]

Source means that current flows into the optocoupler led? Then you just need to limit the amount of input current.
Sink means that current must flow from the optocoupler? Then the led can't provide this and you will have to add an external diode.
Do I understand you correctly?

[sımışka]

Actually, Inputs and outputs in PLCs can be made according to source or sink connection. For example, when the COM of the inputs is connected to +24, our signal must be - triggered so that the input is triggered. The input polority is important now that the opto I use is single photodiode. How can I automatically connect the optocoupler to the anode or cathode by understanding that the terminal that connects to the COM is + or -? Or is there a high-speed dual-color optocoupler?

[Kirill V.]

Does your board know which input mode is currently being used - sink or source? Is there some indicator of the current mode that it accepts?