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TPS7H1101A-SP: Current limit and current foldback

Part Number: TPS7H1101A-SP

Two different pins of the device require different resistance values to set the overcurrent limit (PCL) and the fold-back current limit (RCS). The CS pin resistor sets the fold-back current level and shorting CS low will disable the foldback current limit. I plan to short CS to ground to disable the foldback current limit, what do i need to do with the PCL resistor if i short CS to ground disabling the fold-back current level?

  • Hi Josh,

    1. PCL pin (programmable current limit) A resistor (RPCL) connected from PCL pin to gnd set the current limit set point using equation # 4 on pg. 17 in datasheet. ( see section PCL)
    For example if in your application you need max current of 0.5A then RPCL based upon equation #4 will set the current limit. Similarly if your application requires 3A load thus one can set the current limit point based upon eq. 4 for that condition.
    2. Shorting the CS pin low will disable the foldback current limit. i.e. what ever the current limit is set at for example at 3A, then under short circuit condition current limit will be at 3A. ( no foldback)
    3. If CS pin is high then under short circuit condition if current limit at 3A based upon RPCL value i.e. resistor from PCL pin to gnd , then under short circuit output current will fold back to 1.5A. i.e. 50% of set current limit point.