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PLC 24V PWM Output to 5V PWM microcontroller logic

PLC 24V PWM Output to 5V PWM microcontroller logic

I have a problem with conversion 24V PWM (up to 5kHz) signal (PLC output signal 0.5A) to 5V PWM H-bridge (logic input 10mA). I have an idea to make a voltage divider (serial resistors connection 1,9k and 500R), so i have 19V and 5V and 10mA. Would it be sufficient? Is it a good idea? Or maybe should I use some optocoupler or RS-232 to TTL interface? Does anyone faced with such a problem? I would be grateful for help and advice :)

RE: PLC 24V PWM Output to 5V PWM microcontroller logic

Typically in dealing with 5v, you are dealing with solid state circuits, and therefor TTL interface would be best (speed and reliability).

BIN Industrial & PLC Training

RE: PLC 24V PWM Output to 5V PWM microcontroller logic

Thank you for respond! Could you tell me, if the MC1489 or the SN75189 inverter would be a good choice?

RE: PLC 24V PWM Output to 5V PWM microcontroller logic

RS232 to TTL why??

Here is the answer for you.

Opto cuppler is a great idea

Use the FODM124 of Fairchild . connect 2 K ohms between the input diode anode and the 24v PWM
Connect the output collector via 2 K ohms to the 5 V and the Transistor Collector to the Logic input.

Any question forward to : daveross10 at gmail dat com

Good luck

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