This post explains for the green mode PWM chip.
The Part Number is LD7904JGP7.
The function of this semiconductor is Green Mode Power Switch.
The package is DIP 6 Pin Type
Manufacturer: Leadtrend Technology
Preview images :
The LD7904JGP7 is a green mode PWM chip integrated with a 700V MOSFET in a DIP-6 package. It’s operating at fixed frequency of 100KHz. With multi-functions built-in this IC , such as high voltage startup, OLP/OVP/OTP protection, internal current mode slope compensation, and green-mode power-saving operation under light load or no load condition, this highly integrated device provides high efficiency, low external component counts.
1. Built-in 700V Power MOSFET
2. Built-in High Voltage startup circuit
3. Fixed Switching Frequency at 100KHz
4. Frequency Trembling for EMI improve
5. Internal High Voltage Startup Circuit
6. Under Voltage Lockout (UVLO) on VCC Pin
7. Current Mode Control with Slope Compensation