ZHCSLZ3B May 2020 – June 2021 TPS543820
PRODUCTION DATA
The MODE pin is used to select between four different soft-start times. This is useful if a load has specific timing requirements for the output voltage of the regulator. A longer soft-start time is also useful if the output capacitance is very large and would require large amounts of current to quickly charge the output capacitors to the output voltage level. The large currents necessary to charge the capacitor can reach the current limit or cause the input voltage rail to sag due excessive current draw from the input power supply. Limiting the output voltage slew rate solves both of these problems. The example design has the soft-start time set to 1.0 ms. With this soft-start time the current required to charge the output capacitors to the nominal output voltage is only 0.14 A.