SD4844 PDF – Current Mode PWM Controller

Part Number: SD4844

Function: Current Mode PWM Controller

Package: DIP 8 Pin Type

Manufacturer: Silan Microelectronics

Images:SD4844 pdf


SD4844 is a current mode PWM controller with low standby power and low start current for power switch. In standby mode, the circuit enters burst mode to reduce the standby power dissipation. The switch frequency is 67KHz with ±2.5 KHz jitter frequency for low EMI.

The stress on transformer during power on is reduced by the builtin 15ms soft start circuit to avoid the saturation of transformer. SD4840/4841/4842/4843/4844 includes under voltage lock-out, over voltage protection, leading edge blanking, over current
protection and the temperature protection. The circuit will restart automatically until the system is normal after the protection is active.


SD4844 pinout datasheet


1. Lower start-up current (Typ.6μA)
2. Frequency jitter for low EMI
3. Overcurrent protection
4. Overvoltage protection
5. Undervoltage lockout
6. Built-in temperature protection
7. Built-in high voltage MOSFET
8. Auto restart mode
9. Built-in soft start
10. Burst mode operation
11. Cycle by cycle current limit

SD4844 PDF Datasheet