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TPS7A52: Good choice for battery powered GSM application ?

Part Number: TPS7A52


We are considering TPS7A52 as LDO for GSM module that requiers typ 3.8V and is 3.3V min. Max current pulse will be 2A.

I have two concerns:

1) Shutdown current: as this is battery powered 25µA in "GND pin current" max seems really bad for us and I don't really understand what is behind this figure, especially looking at Figure16. Is it just a typical vs worst case value explanation ?

2) Behavior when Vin < (V_OUT + VDO)? During high current pulse and low temperature condition, I guess my battery voltage could go below maybe 3.6V. If the LDO was set to Vout=3.7V what would happent then? Undefined behavior? I just need Vout>3.3V in this case.

Thank you for help,


  • Hi Thomas, 

    The GND pin current is the difference between the input current and the output current and it includes the quiescent current in the measurement - which is the current necessary to power the internal circuitry.

    I am not sure I understand your question about the typical v best case scenario, could you please provide more info?



  • Hi Juliette,

    What I'm looking for is the standby current typical and worst case value. I think Figure 16 is showing typical value for different temperatures and my understanding is that in table on page 6 the max value for last line of "GND pin current" might be the worst case value for shutdown current. I'm I correct? I would be surprised by such difference (1µA typ 25µA max)!

    Have a good day,


  • Hi Thomas,

    The Figure you see will be a typical case scenario of a nominal part. This is what you will likely see on your device. 

    What is shown on the EC table is the worst case scenario, and a pessimistic value on what the GND pin current can be. 

    As for your second point, your LDO will track Vin if Vin were to fall below regulation. 

    Vout = Vin -Vdo. Vdo = dropout voltage, which scales with your load. 

    Note: If your battery were to recover, your output will overshoot-as is typical of any LDO performance.