Product Specification
Highly-Integrated Green-Mode PWM Controller
voltage over 0.92V, the PWM output will be turned on
again. The hysteresis window for ON/OFF is around
0.2V.
SG6846
RT pin drops below 1.065V, the SG6846 will be turned
off. There are two options for the protection modes,
please see ORDER INFORMATION.
Noise immunity
VDD Over-voltage Protection
VDD over-voltage protection is built in to prevent
the controller from over-voltage destruction. When VDD
voltage is over 23.6V, the SG6846 is latched off.
Noise from the current sense or the control signal
may cause significant pulse width jitter, particularly in
continuous-conduction mode. Slope compensation helps
alleviate this problem. Good placement and layout
practices should be followed. The designer should
avoiding long PCB traces and component leads.
Compensation and filter components should be located
near the SG6846.
Over-temperature Protection
An external NTC thermistor can be connected from
the RT pin to GND. The impedance of the NTC will
decrease at high temperatures. When the voltage of the
© System General Corp.
Version 1.0(IAO33.0008.B0)
- 10 -
www.sg.com.tw
Sep. 30, 2004
ETC [ ETC ]
