SD6109

2.

Remote Switch Control (PSON)

The PC generates the remote switch control signal which is connected to PSON. When the control signal is low,

PC power is on. And when the control signal is high, PC power is off..

3.

AC Fails Detection (UVAC)

The AC line voltage is coupled from the primary side to the secondary side through the main transformer, and

UVAC is connected to the secondary side by a resistor. When UVAC voltage drops below 0.7V and maintains

this situation over 200us, the PG signal will be pulled low , and it indicates that the AC line is power-down. The

voltage amplitude of the PWM switching signal from the secondary side is proportional to the AC line voltage.

Adjusting the ratio of the voltage divider can set the threshold for the power-down.

4.

Over Power Protection (OPP)

The over power protection is designed to detect over power and short circuit.. When the voltage of OPP is higher

than 2.4V and maintain this situation over 7msec, PG will be pulled low and the power outputs will be locked

5.

Negative Voltage Protection (NVP)

The negative voltage protection is designed to provide under voltage protection for negative voltage output.

Overload and short circuit can cause under voltage of negative voltage output.. When the voltage of NVP is

higher than 2.1V and this situation exists for longer than 7msec, the power outputs will be off and be locked.

Adjusting the resistor will set the threshold for locking the power outputs off. The threshold is determined by:

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.1

2009.02.23

Http://www.silan.com.cn

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