LinkSwitch LNK306 soft start with optocoupler feedback

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I'm using the LNK306 on a 6W unisolated power supply design, with the optocoupler feedback topology (page 3, High-Side Buck - Optocoupler Feedback -
On the output, I got a pretty large capacitance (around 680µF).

However, the documentation doesn't specify where to put a soft-start capacitor for the opto-coupler feedback circuit (there is an example on page 10, but for High-Side Buck - Direct Feedback topology).

Any help would be appreciated.
Best regards

Hi pxidr,
You may try to add capacitor in parallel with Vz to have soft-start in case you have auto-restart issue.

Thank you, there is any usual value for this cap?