SLUS829G August 2008 – February 2020 UCC2897A
PRODUCTION DATA.
When the line-overvoltage protection is triggered in the UCC2897A controller, the gate-drive signals are immediately disabled. At the same time, the slow discharge of CSS initiates. While the soft-start capacitor discharges the gate-drive signals remain disabled. Once VSS = 0.5 V and the overvoltage disappears from the input of the power supply, operation resumes through a regular soft start of the converter as it is demonstrated in Figure 21. The pulses of OUT and AUX stop if one of three conditions is met: