Notification 646 - Clamp capacitor not found in the database 

CATEGORY

ISSUE / RESULT

FIX / REFERENCE(S)

Information

For a primary side regulation based device like LinkSwitch-HP, the clamp has to take into account the settling time of the drain voltage ring (to ensure regulation) and the peak drain voltage (to avoid damaging the primary Switch). Under these conditions, a range of acceptable values of the clamp capacitor is calculated by PIExpert and finally, the optimum clamp capacitor is selected from this range. The clamp capacitor selected for this design is out of the range of acceptable values calculated by PIExpert.

• Pick a capacitor within the acceptable range or add an appropriate capacitor to the capacitor database (if unavailable).