This post explains for the semiconductor SD4841.
The Part Number is SD4841.
The function of this semiconductor is (SD4840 – SD4844) Current Mode PWM Controller.
Manufacturers : Silan Microelectronics
Preview images :
SD4840/4841/4842/4843/4844 CURRENT MODE PWM CONTROLLER WITH BUILT-IN HIGH VOLTAGE MOSFET DESCRIPTION SD4840/4841/4842/4843/4844 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. FEATURES * Lower start-up current (Typ.6μA) * Frequency jitter for low EMI * Overcurrent protection * Overvoltage protection * Undervoltage lockout * Built-in temperature protection * Built-in high voltage MOSFET www. […]