OWON ODP3031 DC Power Supply Output Voltage Display Problem

[ramin110]

Hi everyone.
First of all sorry for my English.

I did some experiences with my digital power supply to step up voltage from 30 voltage to higher voltage and after doing some examples I figure out output voltage display on power supply LCD is not showing correctly and always shows around 2.475 voltages on it.
This problem occurred when I use a capacitor and a coil directly connected to power supply output and bouncing wires causes back EMF field and produce very high voltage back to my power supply output but in the output of power supply a very big diode connected to prevent back emf (I thing!).

Here is a list of power supply behaviors:
1.The output voltage and current limiting working fine.
2.The output sensing wires working fine.

On the main board one IC called ( MPC3901A) (Low Cost Power Monitor Reference) doing ADC jobs and when I put a resistor on the ref pins the LCD display changes it's measurement. Also 4 (SGM 8272) High Voltage Rail-to-Rail Output Operational Amplifiers ICs.
I took a picture and attached it here so you can understand better than my poor English.

I will appreciate any help from you guys to help me fixing my power supply. 

There is a topic about this power supply with some taken photos.
https://www.eevblog.com/forum/testgear/odp3032-experience/

Best regards
Ramin

[ramin110]

updates:
d32e is a DAC8532 (Dual Channel, Low Power, 16-Bit, Serial Input DIGITAL-TO-ANALOG CONVERTER).

when I change the voltage, pin 4 ( Vout b) voltage is changing respect to voltage coming from front panel mcu but pin 3 (Vout b) is always same and when I set the voltage output to 2.504 as same as LCD output voltage display both pin 3 and pin 4 voltage is same.

[ramin110]

The problem is fixed now.

After Changing the MCP3901A IC the LCD Display Works fine. The owon company was king enough to send me a free MCP3901A IC to replace it.

Thanks