Analog Discovery 2 Wavegen Latched Low

[postmaster87]

Hello,

I have a Discovery 2 that has both Wavegen channels latched a -5.4 V. I checked the Waveform project settings with another Discovery 2 and it generating signals correctly. I believe the only other time we used it was as a scope an it functioned correctly. Please advise.

Best,
Matt 

[attila]

Hi @postmaster87

Under Settings menu Device Manager try Calibrate / Reset / Load factory to restore the factory calibration.

In case it is is still not working the Wavegen output amplifier could be damaged.

[postmaster87]

Hello,

Thanks for the quick response. We ran through the calibration and everything seems to be working correctly except the function generators. Can you advise on troubleshooting the output amplifier?

Thanks,

Matt

[attila]

Hi @postmaster87

Here you can find the schematic:
https://reference.digilentinc.com/analog_discovery_2/refmanual#figure_19

1. On the audio jack you can verify the AWG output after first, I/V amplifier.
2. Verify the AVCC5V5_AWG_SW and AVCC-5V5_AWG_SW, +5.5V and -5.5V
3. On pin 3 of IC16/IC17 you should see the offset of channel 1/2, setting -5V...5V offset you should see 0V...0.6V here
4. When the board is unpowered, verify the PTCs highlighted above the ICs, which should be about 50 Ohms.

Bottom layout, under the 30pin connector.