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PXI trigger level to low

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Any suggestions on how to trigger a camera digital input using PXI?


My camera has opto-isolated digital inputs and requires  3-25V input for min. 20 msec to turn high.

Power and digital I/O connection for A50/A70 and A400/A500/A700 (custhelp.com)

Right now I trigger the camera using PFI from waveform generator,since the trigger needs to set in relation to generated waveform, but this works only for 90% of the time, since the pfi level is too low (2.9VDC open).


I would prefer a fast switching solution, so no reed relays or additional optocoupling please.


Generator: PXI 5441

Digital IO(crazy connector) PXIe 6515 available

Matrix(reed) PXIe 2541 available


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Message 1 of 3
Accepted by topic author Quiztus2

Do you want to avoid optocouplers for their propagation delay?


Any component in the path is going to add a propagation delay than having nothing. The question would be how much delay is tolerable. You need to convert the 0.2V-2.9V signal levels into CMOS levels (something like mc74vhc1gt126 with a TTL input and CMOS output with just 3.5ns prop delay at 5V)

Soliton Technologies

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Message 2 of 3

Thanks a lot, that one gave me headaches. Didn't know of their existence: Noninverting Buffer / CMOS Logic Level Shifter - TTL−Compatible Inputs

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