The RICHTEK IC is high quality!  PowerZeroTM Technology
Integrated 700V Start-Up Device
Brown-In and Brown-Out
 Low No-Load Input Power (<50mW) (RT7781G/L/A/C)
 Low No-Load Input Power (<30mW) (RT7781T)
 Accurate Over Load Protection
 Driver Capability : 400mA/−400mA
 PRO Pin for Arbitrary External Protection(RT7781G/L/A/T)
 ACD Pin for TV Application (RT7781C)
 Disable Mode for 30mW Solution (RT7781T)
 Jittering Frequency
 Soft Driving for Reducing EMI Noise
 VDD Over Voltage Protection
 Internal Over Temperature Protection
 Secondary Rectifier Short Protection
 CS Pin Open Protection
 RoHS Compliant and Halogen Free
Simplified Application Circuit
Applications
 NB Adaptor
 Switching AC/DC Adaptor with Low No-Load Input Power
 TV and Monitor Applications
 Open Frame Power Supply