JAJSIO3A February 2020 – September 2020 TPS546B24A
PRODUCTION DATA
To control the inrush current needed to charge the output capacitor bank during start-up, the TPS546B24A implements a soft-start time programmed by the Section 7.6.49 command. When the device is enabled, the reference voltage ramps from 0 V to the final level defined by the following at a slew rate defined by the Section 7.6.49 command:
The TPS546B24A devices support several soft-start times from 0 ms to 31.75 ms in 250-µs steps (7 bits) selected by the Section 7.6.49 command. The tON_RISE time is selectable by pin-strapping through the MSEL2 pin (eight options), PMBus programming, or both.
During soft start, when the PWM pulse width is shorter than the minimum controllable on-time, pulse skipping can be seen and the output can show larger ripple voltage than normal operation.