December 2009

© 2009 Fairchild Semiconductor Corporation

www.fairchildsemi.com

FAN6300A/H • Rev. 1.0.1

FAN6300A / FAN6300H

Highly Integrated Quasi-Resonant Current Mode

PWM Controller

Features

High-Voltage Startup

Quasi-Resonant Operation

Cycle-by-Cycle Current Limiting

Peak-Current-Mode Control

Leading-Edge Blanking (LEB)

Internal 5ms Soft-Start

Over Power Compensation

GATE Output Maximum Voltage

Auto-Recovery Over-Current Protection(FB Pin)

Auto-Recovery Open-Loop Protection(FB Pin)

VDD Pin and Output Voltage (DET Pin)

OVP Latched

Low Frequency Operation (below 100kHz) for

FAN6300A

High Frequency Operation (up to 190kHz) for

FAN6300H

Applications

AC/DC NB Adapters

Open-Frame SMPS

Description

The highly integrated FAN6300A/H of PWM controller

provides several features to enhance the performance

of flyback converters. FAN6300A is applied on quasi-

resonant flyback converters where maximum operating

frequency is below 100kHz. FAN6300H is suitable for

high-frequency operation (up to 190kHz). A built-in HV

startup circuit can provide more startup current to

voltage exceeds the turn-on threshold voltage, the HV

startup function is disabled immediately to reduce

power consumption. An internal valley voltage detector

ensures power system operates at quasi-resonant

operation over a wide-range of line voltage and any

load conditions, as well as reducing switching loss to

minimize switching voltage on drain of power MOSFET.

To minimize standby power consumption and light-load

efficiency, a proprietary green-mode function provides

off-time modulation to decrease switching frequency

and perform extended valley voltage switching to keep

to a minimum switching voltage. The operating

to 8µs in FAN6300A and 13µs to 3µs in FAN6300H, so

FAN6300H can operate at higher switching frequency

than FAN6300A.

FAN6300A/H controller also provides many protection

functions. Pulse-by-pulse current limiting ensures the

fixed-peak current limit level, even when a short circuit

occurs. Once an open-circuit failure occurs in the

feedback loop, the internal protection circuit disables

the turn-off threshold voltage, the controller also

disables PWM output. The gate output is clamped at

18V to protect the power MOS from high gate-source

prevents the system frequency from being too high. If

the DET pin triggers OVP, internal OTP is triggered and

the power system enters latch-mode until AC power is

removed.

The FAN6300A/H controller is available in the 8-pin

Small Outline Package (SOP) and the Dual Inline

Package (DIP).