4DSP Products Technical support

Are there any known-issues/errata with the FMC151 DAC outputs?  We are seeing that any waveform that we output on DAC 'C' is inverted from the original waveform that we send. However, the waveform on DAC output 'D' is correct (i.e. not inverted).

                                DAC 'C' ==> O-scope ==> inverted
Same Waveform ==<
                                DAC 'D' ==> O-scope ==> _not_ inverted

It seems as if somehow the differential P/N pairs were hooked up incorrectly on the board for DAC 'C'.

Running the identical FPGA design and FMC150App with the FMC150 card does not have this issue. So therefore it has to be an issue with the FMC151.

This topic is being closed because the issue is considered as resolved by 4DSP. Feel free to create a new topic for any further inquiries.

Gotta love "features" like this...


[b]Edit: [/b]It would be cool if you somehow indicated this on the block diagram (Figure 1). Like an inversion bubble on the channel C output.

Hi Jonathon,


The P/N pair of output C is indeed inverted. This is noted in section 4.5 of the User Manual.


Best regards,
Peter