Green-Mode PWM Controller with High Voltage Startup Circuit
Features
l High-Voltage (650V) Startup Circuit
l Very Low Startup Current (<30uA)
l Under-Voltage Lockout (UVLO)
l 100mW Standby Power
l Non-Audible-Noise Green-Mode Control
l 65KHz Switching Frequency with Jittering for Reducing EMI
l Cycle-by-Cycle Peak Current Limiting
l Internal Leading-Edge Blanking
l Internal Slope Compensation
l Gate Output Maximum Voltage Clamp
l Internal 6mS Soft Start
l Soft Driving for Reducing EMI
l AC Input Brownout Protection with Hysteresis
l Over-Voltage Protection (OVP) on VCC pin
l Over-Load Protection (OLP)
l External Shutdown Pin (Latch) for Aux. Winding OVP and Accuracy OTP
l 500mA Driving Capability
l SOP-8 /SOP-7/DIP-8 Green Package
Description
The GR8875NR series is a highly-integrated, low startup current, current mode PWM controller with
Green-mode function, high-voltage startup circuit, and provides several protections such as OLP, OVP, and OCP for fault conditions. A high-voltage current source supplies the startup current and the traditional start up resistance can be saved in order to reduce the startup power loss. The controller also includes the leading-edge blanking of the current sensing, internal slope compensation and cycle-by-cycle peak current limiting. It is also integrated soft driving for reducing EMI, gate output voltage clamp function for protecting power MOSFET.
Applications
l Adaptor/ Open Frame Power Supply
l LCD Monitor/TV Power Supply
Application Circuit
Package
