Non-Isolated LNK3205 15V supply turn off behavior

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I have been working on a non-isolated 15V supply using the LNK3205. I am having trouble with the turn off behavior of the supply. When I cut the AC power to the circuit the 15V output starts to drop as I would expect, but then it behaves as though it is trying to start up again a couple of times. After about 800mS it finally gives up and the output slowly decays as the energy stored in the output caps is drained. I've included a waveform of the output as well as schematic of my circuit. Note that I have a full wave bridge rectifier elsewhere in the design that supplies the rectified AC to this circuit.

My primary goal is to keep the output below 5V after I cut AC power to the circuit. I've added a cap around the feedback resistor (Cnew in the SCH) to improve the turn on performance but it hasn't had an effect on the turn off behavior.

output waveform470.51 KB
Schematic239.09 KB

Hi mike,

I just need to know a few things to better evaluate this problem:

Can you probe the voltage across C38 after AC cutoff?
On the waveform you provided, what is thr loading condition? No load or full load? Also what are your output power specifications?