Hi Team, We have designed the dual power supply using the IC TPS65131 to get +12V and -12V with 5v as input.
For this we have Chosen the below resistor values:
R1=976K ohm, R2=110K ohm as per the relation R1=R2*((V_pos/V_ref)-1)
R4=133K ohm, R3=1.3M ohm as per the relation R3=-R4*(V_neg/V_ref)
In our schematics (attached), R1=R34, R2=R36, R4=R35, R3=R38
WEBENCH TOOL shows the same resistor values as per the above calculations for +/-12V.
But we obtained the following values when a 5V input is supplied without any load.
Positive voltage = +16.5 V
Negative Voltage = -17.8 V
Please let me know the changes/updates required in the design, so as to get the positive voltage of +12V and the negative voltage -12V.
I really appreciate your help in this. Thank you.