Hallo,
we have an application where the input voltage on the LV Port is 3V and at the HV Port it should be 12V ( which is transformed to 48V on the other side of transformer where the load is positioned)
I use two phases as in Eval board; the rated current is 30 Amps on the LV Port in buck and boost mode. So that means 15Amps per channel. To get 45mV VCS we use a 3mR shunt resistor
in each phase.
The problem is as follows: the voltage at the IsetA pin is generated by a DAC. this voltage is correct at the IsetA pin for 5A Current we have 375mV exactly. that means 7,5mV Vcs.on each half.and results in a current of 2,5A / phase.
The problem is that I can measure nearly exact 7,5mV between CSA CSB pins, but on the other pair i measure only 6,8mV. so this results in loss of about 250mA of current , which is a 5% deviation.
We have on the csa and csb Inputs 47pF to ground and a cap for Compensation of inductance of shunt with 100nF betwenn the pins.
This deviation is at 20 Amps about 800mA although there is 1,5V exactly on ISETA.
Do you have a proposal to solve this issue?
Thank You!