
May 2011
2011 Fairchild Semiconductor Corporation
www.fairchildsemi.com
FAN6863 Rev. 1.0.1
FAN6863
—
Highly
Integrated
Green-Mode
PWM
Controller
FAN6863
Highly Integrated Green-Mode PWM Controller
Features
Low Standby Power: Under 0.1W
Low Startup Current: 8A
Low Operating Current at Green Mode: 600A
Peak-Current Mode Operation with Cycle-by-Cycle
Current Limiting
PWM Frequency Continuously Decreasing with
Burst Mode at Light Loads
VDD Over-Voltage Protection (OVP)
Constant Output Power Limit (Full AC Input Range)
Internal Latch Circuit (FAN6863L) for OVP, OTP
SENSE Pin Short-Circuit Protection (SSCP)
Fixed PWM Frequency (65KHz) with Frequency
Hopping
Feedback Open-Loop Protection: 60ms Delay
GATE Output Maximum Voltage Clamp: 13.5V
Soft-Start Time: 5ms
Soft Driving for EMI Improvement
Full Range Frequency Hopping
Internal OTP Sensor with Hysteresis
GATE Driving Capability: 400mA
Applications
General-purpose switched-mode power supplies and
flyback power converters, including:
Power Adapters
Open-Frame SMPS
SMPS with Surge-Current Output, such as for
Printers, Scanners, Motor Drivers
Description
A highly integrated PWM controller, FAN6863 provides
several features to enhance the performance of flyback
converters. To minimize standby power consumption, a
proprietary Green Mode provides off-time modulation to
continuously decrease the switching frequency under
light-load conditions. Under zero-load conditions, the
power supply enters Burst Mode, which completely
shuts off PWM output. Output restarts just before the
supply voltage drops below the UVLO lower limit. Green
Mode enables power supplies to meet international
power conservation requirements.
The FAN6863 is designed for SMPS and integrates a
frequency-hopping function that helps reduce EMI
emission of a power supply with minimum line filters.
The built-in synchronized slope compensation provides
proprietary sawtooth compensation for constant output
power limit over universal AC input range. The gate
output is clamped at 13.5V to protect the external
MOSFET from over-voltage damage.
Other protection functions include SENSE pin Short-
Circuit Protection (SSCP), VDD Over-Voltage Protection
(OVP), and Over-Temperature Protection (OTP). For
OTP, an external NTC thermistor can be applied to
sense the ambient temperature. When VDD OVP or OTP
is activated, an internal latch circuit latches off the
controller. Protection types shown in Table 1.
Table 1. Protection Type
Part
Number
OVP
OLP
OTP /
OTP2
SSCP
FAN6863
Latch
A/R
Latch
A/R
FAN6863L
Latch
A/R
FAN6863R
A/R
Ordering Information
Part Number
Operating
Temperature Range
Package
Packing Method
FAN6863TY
-40 to +105°C
6-Lead, SuperSOT-6, JEDEC M0-193,
1.6mm Wide
Tape & Reel
FAN6863LTY
FAN6863RTY