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Combining pins to source / sink more current

Altera_Forum
Honored Contributor II
‎02-08-2018 03:42 AM
1,408 Views

Hi,  

 

I have a Cyclone V that needs to be able to briefly source and sink current ~60mA for 1 to 8us before returning to the microamps range. I see that the IO pin max ratings are -25mA to 40mA.  

 

Given that I'm outside the range even for a short amount, can I use two IO pins and connect them together in order to achieve a greater current amount to sink or source i.e. summing the currents to get -50mA to 80mA?
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Altera_Forum
Honored Contributor II
‎02-08-2018 08:31 AM
389 Views

Hi, 

 

we cannot guarantee the FPGA reliability. 

Not Recommended. 

 

Best Regards, 

Anand Raj Shankar 

(This message was posted on behalf of Intel Corporation)
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Altera_Forum
Honored Contributor II
‎02-08-2018 10:38 AM
389 Views

It is difficult to guarantee that the current will be split evenly between the two pins. You could end up with more current on one pin than on the other. Check also if there is a limit on the full I/O bank current. 

I think it would be more reliable to use an external buffer or a little transistor to do the job.
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