LD7660J PDF Datasheet – Low Power Off-line Switcher

Part Number: LD7660J, LD7660JGN

Function: Low Power Off-line Switcher

An off-line switcher, also known as an offline switch-mode power supply (SMPS) controller or off-line flyback controller, is an integrated circuit (IC) or semiconductor device used in power supply designs to convert high-voltage AC (alternating current) mains voltage to a lower DC (direct current) voltage for various electronic devices. These controllers are specifically designed for offline power supplies, which operate directly from the mains power source, typically at voltages such as 100V to 240V AC.

Package: DIP 8 Pin Type

Manufacturer: Leadtrend


LD7660J pdf pinout


The LD7660J integrated a 600V power MOSFET and a current mode PWM controller in a DIP-8 package. It’s operating at fixed frequency of 65 kHz. It provides important functions needed for a low output power applications such as leading-edge blanking of the current sensing, internal slope compensation, and green-mode power-saving operation under light load or no load condition.

This highly integrated device provides the users a high efficiency, low external component counts, and low cost solution for low power adaptor or charger applications. The special green-mode control is not only to achieve the low power consumption but also to offer a non-audible-noise operation when the LD7660J is operating under light load or no load condition.


1. Built-in 600V/1A Power MOSFET

2. Secondary-side/Primary-side feedback control

3. Switching Frequency at 65KHz

4. Fixed Internal Frequency Trembling

5. Built-in Load Regulation Compensation

6. Built-in Slope Compensation with 75% max duty-cycle

7. Low Startup Current (<20μA)

8. Current Mode Control with Cycle-by-Cycle Current Limit

9. Non-audible-noise Green Mode Control

LD7660J datasheet


1. AC to DC Conversion: Off-line switchers take the high-voltage AC input from the mains and convert it into a lower DC voltage suitable for powering electronic devices. This process involves rectification, filtering, and voltage regulation.

2. Switching Operation: Off-line switchers use high-frequency switching to convert the AC input voltage into a high-frequency AC signal. This allows for smaller and more efficient transformers and reduces the size and weight of the power supply.



1. Switching AC/DC Adaptor

2. LCD TV or PC Standby Power


LD7660J PDF Datasheet