ZHCSLD3B May 2020 – December 2023 TPS566231 , TPS566238
PRODUCTION DATA
The TPS566231 and TPS566238 have an external SS pin to set the soft-start time. When the EN pin becomes high, the soft start function begins ramping up the reference voltage to the PWM comparator.
If the application needs a longer soft-start time than 0.5 ms, the time can be set by connecting a capacitor on the SS pin. When the EN pin becomes high, the soft-start charge current (ISS) begins charging the external capacitor (CSS) connected between SS and ground. The devices track the lower of the internal soft-start voltage or the external soft-start voltage as the reference. The estimated equation for the soft-start time (TSS) is shown in Equation 2:
where