SBVS343 March 2019 TPS7A78
ADVANCE INFORMATION for pre-production products; subject to change without notice.
An overvoltage protection circuit is always monitoring VLDO_IN to prevent it from over charging above 5.75 V. An overvoltage event can accrue during a load transient when a heavy load is abruptly removed. The overvoltage protection is then engaged and stops the switch caps from switching until the excess charge on CLDO_IN is removed by the load. This why LDO_IN pin must not be driven externally. This protection behavior is particularly present during heavy load transient on devices with a 5.0-V output voltage as their CLDO_IN voltage are kept 600 mV (typical) above their CLDO_OUT and close to the over voltage threshold of 5.75 V. See the Dropout Voltage Regulation section for more details on the device dropout voltage regulation.