Why does my digital output give 1V instead of 5V?

[Finkler]

I have a PCI-6030E. When I look at its digital output at port0/line0, I see 1V instead of 5V when it's 'high'. It read 0V when 'low'.

Any ideas?

Amit 

[rpursley8]

How are you looking at the signal?  The digital lines are very limited when it comes to output current.  You need to look at it with a high impedance probe.

[Finkler]

I am looking at it with a simple voltmeter, which should have a very high impedance by definition.

Amit 

[jschwartz]

Hi Amit,

If you look at other channels, do you see 1 V as well?  I would make sure that other channels behave the same way. Also, I would make sure that you are using Test Panels in Measurement and Automation Explorer.  If you suspect that your card is malfunctioning, you can go to ni.com/ask and create a service request.  Make sure to change the question type to Returning hardware for repair/replacement/calibration.  Then call 1-866-275-6964 with that service request number to send in your board for repair.

[rpursley8 · Accepted solution]

The only other thing that I can think of is that you do not have a good connection to DGND when measuring or the line is possibly configured as an input.  If this isn't the case, then the card may be defective.

Message Edited by rpursley8 on 08-20-2009 10:09 AM