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Can USB-6009 digital output (open collector) external pull-up use its on board external +2.5 V output?

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Can USB-6009 digital output (open collector) external pull-up use its on board external +2.5 V output?

 

Hello,

 

I want to config USB-6009 digital output to have +2.5 V as high and 0 V as low digital output. I know I can config USB-6009 digital output to open collector with external pull-up resistor, which can be applied with +2.5 V power source.

 

My question is: Can I use USB-6009 on board +2.5 V output as the pull-up resistor power source? What resistance is a good number for the pull-up resistor if I can use this configuration?

 

Thank you very much for the help,

 

Cathy

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Accepted by topic author Cathymin

Hi Cathy,

 

The USB 6008 digital front end looks like this:

 

 

2010-01-26_110938.png

 

So, there is actually a 4.7 kOhm internal pullup resistor to 5V when the device is configured for open collector.

 

If you want to output 0-2.5 V, I would look into using a 4.7 kOhm bias resistor between DO and Ground (depending on the rest of your circuit).

 

 

Best Regards,

John Passiak
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Thank you very much John.
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