I have a power supply based on TNY280, because the 24V output have a big capacitor, during start up the power IC will falling to autorestart mode, so I created an artifical feedback by MCU when the target 24V output rising to about 7V (7V for MCU is ok to run).
The problem is, because HW reset of MCU, the artifical feedback come out 950ms later, that means the artifical feedback doesn't arrive to TNY280 during the first startup 64ms.
Strange thing come out, the delayed artifical feedback can make the power IC run again, and the power IC runs only for about 40ms,
Can you pls tell me the reason?
In data sheet, I only see 64ms without feedback, come out 2.5s MOSFET off.
Is there some other thing in the state machine for the auto-restart?
Thanks in advance.