Hello, thank you for your reply.
6. When LK3 is at posistion D. The Vref of AD5686 is 5V at(TP2) but external reference is not connected
Would you be able to do a short circuit test on possible sources of the mysterious 5V? Please try the following:
- between TP2 and U4's pin6 (ADR435's Voutpin)
- between TP2 and VDD
Do note that there is no chip at U4. Anyway I test all 6 pin and there is no short circuit to any of them when LK3 is at position D.
No short circuit to internal VDD or external VDD too.
I decided to purchased EVAL-SDP-CS1Z and connected to EVAL-AD5686RSDZ.
jumper setting LK1 -LK6
A, A, C, B, B, B respectively
Current drawn when 6V connected 0.20-0.21A
After connecting USB to SDP current increased to 0.35-0.37A
After opening software & sync connected 0.43-0.44A
DAC output at start up 2.51V for AD5686R & 20-40mV for AD5686 on the board
After trying to write to and update DAC n 0.49-0.52A but no change in DAC value althought the SPI bits are shown
Trying again to write to and update DAC n gets a pop up;
System Development platform wait
Waiting for transfer to SDP....
waited for a long time but does not disappear.