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Maximum voltage on USB-6001 DI

Maximum voltage on USB-6001 DI

‎05-25-2021 07:24 AM

With a digital input i read the open colector output from a ic. Pull-up to 12V is 100k Ohm.

In the data sheet i read the usb-6001 input has a 47.5 k Ohm resistor to D GND.

The result is a voltage divider 1:2.1

Is this wiring a problem? (Overvoltage)

 

 

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Re: Maximum voltage on USB-6001 DI

‎05-25-2021 07:56 AM - edited ‎05-25-2021 07:59 AM

Let's do a little math...

Vout = R2/(R1+R2)*Vin = 47.5k/(100k+47.5k)*12 = 3.86V

 

Looks like you should be fine, but I would probably add an optocoupler to better protect the input.

GCentral
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