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LT8708 can't soft startup recover when it's enter to overcurrent state!!!!

Dear teams: 

    I just use lt8708 for double battery applications, Now i just test And find some problem as following:

1. In input i just use a 10A 48V power supply(PS)

2. In Output, a Electronic load for test the LT8708's efficient

3. Setting the IMON_OP current is 1.6A ,simulate the battery Charge current

As following is observed state for LT8708

1. When the Electronic load's current is "0-1.6A",  the PCB output stable voltage 54.7V

2. if  verify the current to 1.7A or above ,the LT87 entry over current protect ,And VOUT side have no voltage

3, if I verfify the current From 1.7A to 0.1A or lower current, The Lt8708 Ouput side can't recover to 54.7V,

4. I use oscilloscope probe check signal, I find SS Pin Voltage just about 180mV, Can't soft startup again

I wan't know How to Implement overcurrent  recovery , For battery supply system, It's very important!

Can anyone answer me ,expect !!!!!

  • Hi fhlxtUpdate,

    The LT8708 responds to exceeding the over-current setting by reducing the output voltage. If the electronic load is set to constant current and the current exceeds the LT8708 current limit setting then the LT8708 will keep reducing the voltage but the electronic load will compensate and keep the current at the set level. This is not a realistic scenario. The electronic load should be set to be resistive and the resistance value determined by the output voltage setting divided by the desired current. The output voltage will then reduce to match the LT8708 current limit setting.

    Additionally, verify FBIN setting, IMON_INP setting and monitor Vin and Vout.