Hello, I have a SYMSI70 gas heater board, which has issues with its primary side power supply, controlled by TOP247Y chip.
When I replace a TOP247Y it explode in 1 second. I have desoldered transformer and measured a winding ratio, so transformer looks like OK.
Transformer:
|Info| Primary | Aux | AB | CD|
|-|----------|----------|-|-|
|Ratio|1|25|40|12|
|Voltage AC|230V|9.2V|5.8V|19V|
|Voltage DC (*1.41)|230V|13V|8.1V|27V|
I have disabled a undervoltage protection of TOP247Y, disconnected secondaries and tried to power it up...
Comment