Over voltage cut off circuit

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Hi Team
We have to design Over voltage cutoff circuit. Following is requirement
Operating voltage : 85-330Vac
Over voltage : 230-300Vac (configurable )
IC : LNK306
Realy on indication : Green color when voltage is below Over voltage
Relay off indication : When Over voltage trigger
Relay operating voltage : 12 Vdc
Please help me with some reference schematic.

Hi abhishekoct18,

Just to confirm your specifications:
If input voltage is between 85 and 230, output voltage is 12V?
if input voltage is greater than 230, power supply is off?

It's difficult to sense line voltage in a buck configuration using LNK3. In a flyback power supply, the line voltage can be sensed indirectly thru the transformer as in Figure 6:


If you need configurable line overvoltage protection, I suggest take a look at InnoSwitch3 family of devices. It has a dedicated line sensing (V pin) that suits your requirement. The bus voltage is directly sensed by the IC.