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Purpose of voltage divider and 50 K resistor in this reference circuit

I am testing my circuit of a single charger for a dual battery system. For that, I am using the LTC4001 combined with the LTC4415 (just as the picture below.)

I don't understand the reason for the 50k resistor. Similarly, I do not get why the 1.5k voltage divider goes to BATSENS.

I understand that the charger needs a BATSENS to know the status of the load, but this configuration makes it so that when BAT1 is disconnectedsome voltage is induced in LOAD1 coming from BAT2. This raises some unexpected behavior in my LOAD1. Is the 50K resistor really necessary? Other dual OR diodes do not consider it.

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  • Is the 50K resistor really necessary? Other dual OR diodes do not consider it.

    The 50k is a path from the LTC4001's BAT pin to BAT1/2 when the ideal diodes are Hi-Z.
    The LTC4415 doesn…

    •   
    Dec 21, 2021 in reply to WladimirDLC +1 suggested
    My system, actually is dual battery system for the same load. But I have a buck converter to 5V where the input is BAT1.

    Does BAT2 have it's own buck converter too?

    If so, are the…

  • Is the 50K resistor really necessary? Other dual OR diodes do not consider it.

    The 50k is a path from the LTC4001's BAT pin to BAT1/2 when the ideal diodes are Hi-Z.
    The LTC4415 doesn't need the 50k; it is specific to this application.
    It must be done to give the LTC4001 a load, or to trickle charge BAT1/2.
    I'll leave that for someone else to answer.

    I understand that the charger needs a BATSENS to know the status of the load, but this configuration makes it so that when BAT1 is disconnectedsome voltage is induced in LOAD1 coming from BAT2. This raises some unexpected behavior in my LOAD1.

    What kind of load do you have?

  • My system, actually is dual battery system for the same load. But I have a buck converter to 5V where the input is BAT1. So, even in the absence of one BAT2, some voltage arrives to the converter, and produces output voltage that I do not need. My goal is that when BAT1 is disconnected no voltage appears on the BAT2 terminal.

  • My system, actually is dual battery system for the same load. But I have a buck converter to 5V where the input is BAT1.

    Does BAT2 have it's own buck converter too?

    If so, are the outputs of both BAT1 and BAT2's buck converter tied to the same load?

    A block diagram would better illustrate your system.

    So, even in the absence of one BAT2, some voltage arrives to the converter, and produces output voltage that I do not need.

    Another method could be to disable the buck converter when a battery isn't connected.