Fixing a charger

[anda]

I am trying to fix a small battery charger. I have had the component out of the board and checked them.except for the optocoupler, the mc358m and and a 6 pin ic with no reading on it. Perhaps a power ic?
The is power up to the transformer but no sound from it.
I have orderet a optocoupler and a mc358m. Dont know how to check them. What can the 6 pin chip be?

The board is a haider hbn3a2004 A B. Cant find it via google.

[xavier60]

The 6 pin IC is possibly a SMPS controller by Richtek or some another brand. Does the IC drive a MOSFET?