TPS7B4253-Q1: Startup behavior of the IC

 Hello,

according to the data sheet, the TPS7B4253-Q1 should be stable at an output capacitance of 10µF to 500µF. However, with our circuit we measure a drop in the startup behavior (without and with load).

With a significantly increased capacitance at the output (150µF electrolytic capacitor in parallel to the 10µF), a different behavior occurs (see Figure).

The supply voltage and reference voltage is present before and has no dips.

[Due to poor resolution: C2(red):reference voltage, M3(left blue): Output voltage(10µF), C3(right blue): Output voltage(160µF)]

Is this behavior known?
By which circuit can a more monotonic behavior be realized?


Thanks for the help

Adrian Schmitt