I'm facing a problem in my circuit with LTC4359, when my output exceed the input voltage LTC4359 stop working.
I would like to mainten my LTC4359 even if my output exceed the input. Theres is a way to do it?
It's strange how the battery became a greater potential than the supply recharging it. This would be temporary, as the battery would eventually discharge to be 30mV less than the supply.…
Hi Bengui, If I understand you right, the LTC4359 is behaving as intended. Remember that the part is an ideal diode controller, and diodes only conduct in one direction. When OUT-IN ≥ 30mV, the LTC4359 turns off the transistor. Can you tell me more about your application and post a schematic? -Aaron
Thank you for your Reply Aaron,
In my application i'm supplyng a system and charging a battery, Vbat exceed Vin and the LTC4359 stop working, as you explain it's a normal behavior of this component. I would like to maintain VIN even if the battery is completly charged and use it only for back-up VIN=0.
It's strange how the battery became a greater potential than the supply recharging it. This would be temporary, as the battery would eventually discharge to be 30mV less than the supply.
I found something that may be closer to what you want using the LTC4412 powerpath controller. If you look at the figure 3 in the datasheet, the circuit is similar to the application you describe. I modified this circuit to behave like you requested:
1) The supply is charging the battery (when VIN + ~300mV > VBAT)
2) VIN has priority over VBAT (CTL tied to VIN)
3) VBAT only used when VIN=0 (VIN < 650mV is the best this circuit can do)
I don’t know what voltages and load current you are working with, so I just picked something. The diode and FET models are also placeholders. I’ll give you the simulation file so you can play around with it. Let me know if this works. -Aaron4412 4359 EZ question.asc
Thank you for your reply Aaron,
I will see the option that you suggested to me, for my application the LTC4359 does not seem to work as well, I have a confirmation for a few minutes and then Vbat feeds the system.
LTC4412 will not work for my system, my Vin is 51V.