DESCRIPTION
SD686X is current mode PWM+PFM controller with built-in highvoltage MOSFET used for SWPS, 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 25~67KHz with jitter frequency for low EMI.
Built-in peak current compensation circuit makes the limit output
power stable even with different input AC voltage. Limit output
power can be adjusted through the resistor. Maximum peak current
compensation during power-on reduces pressure on transformer to
avoid saturation, the peak current compensation will decrease for
balance after power-on.
It integrates various protections such as undervoltage lockout,
overvoltage protection, overload protection, lead edge blanking,
primary winding overcurrent protection and thermal shutdown. The
circuit will restart until normal if protection occurs.
FEATURES
* Energy Star 2.0 standard
* Lower start-up current (3mA)
* Various switching frequency following load for the higher
efficiency
* Frequency jitter for low EMI
* Overvoltage, overcurrent, overload and over temperature
protections.
* Adjustable limit output power
* Undervoltage lockout
* Built-in high voltage MOSFET
* Auto restart mode
* Peak current compensation
* Maximum peak current compensation for initialization
* Burst mode
* Cycle by cycle current limit