Output voltage is detected by controller through VS pin, However, it is not recommended to probe VS pin directly as the noise introduced by probing could cause protection mis-triggering. Instead, AUX winding voltage can be used for identifying whether OVP happens. If the divided voltage on VS pin exceed OVP threshold for three consecutive pulses, OVP is triggered.

Figure 3-3 OVP Delay to Action

Figure 3-4 OVP Delay to Action (Zoom In)

Figure 3-5 OVP Action

CH2: AUX winding voltage (Vaux), CH1: PWML, CH3: Output voltage.