ZHCSI13J October 2004 – November 2018 TPS75003
PRODUCTION DATA.
The LDO uses an external soft-start capacitor, CSS3, to provide an RC-ramped reference voltage to the control loop. See the Functional Block Diagram. This is a voltage-controlled soft-start, as compared to the current-controlled soft-start used by the buck controllers. The start-up waveform can be approximated by Equation 15:
where
The time taken to reach 90% of final VOUT can be approximated by Equation 16: