March 2010
© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
FAN6754 • Rev. 1.0.2
FAN6754 — Highly Integrated Green-Mode PWM Controller
FAN6754
Highly Integrated Green- Mode PWM Controller
Brownout and V
Limit
Adjustment by HV Pin
Features
High-Voltage Startup
AC Input Brownout Protection with Hysteresis
Monitor HV to Adjust V
Limit
Low Operating Current: 1.7mA
Linearly Decreasing PWM Frequency to 22KHz
Frequency Hopping to Reduce EMI Emission
Fixed PWM Frequency: 65KHz
Peak-Current-Mode Control
Cycle-by-Cycle Current Limiting
Leading-Edge Blanking (LEB)
Internal Open-Loop Protection
GATE Output Maximum Voltage Clamp: 13V
V
DD
Under-Voltage Lockout (UVLO)
V
DD
Over-Voltage Protection (OVP)
Programmable Over-Temperature Protection (OTP)
Latch Circuit (OVP, OTP)
Open-Loop Protection (OLP); Restart for MR, Latch
for ML
Built-in 8ms Soft-Start Function
Applications
General-purpose switch-mode power supplies and
flyback power converters, including:
Power Adapters
Description
The highly integrated FAN6754 PWM controller
provides several features to enhance the performance
of flyback converters. To minimize standby power
consumption, a proprietary green-mode function
provides off-time modulation to continuously decrease
the switching frequency under light-load conditions.
Under zero-load and very light-load conditions,
FAN6754 saves PWM pulses by entering deep burst
mode. This burst mode function enables the power
supply to meet international power conservation
requirements.
FAN6754 integrates a frequency-hopping function
internally to reduce EMI emission of a power supply
with minimum line filters. Built-in synchronized slope
compensation is accomplished by proprietary HV
monitor to adjust V
Limit
for constant output power limit
over universal AC input range. Also, the gate output is
clamped at 13V to protect the external MOSFET from
over-voltage damage.
Other protection functions include AC input brownout
protection with hysteresis and V
DD
over-voltage
protection. For over-temperature protection, an external
NTC thermistor can be applied to sense the external
switcher’ s temperature. When V
DD
OVP are activated,
an internal latch circuit is used to latch-off the controller.
The latch mode is reset when the V
DD
supply is
removed.
FAN6754 is available in an 8-pin SOP package.
Ordering Information
Part Number
Operating
Temperature
Range
Eco
Status
Package Packing Method
FAN6754MRMY
-40 to +105°C Green 8-Pin, Small Outline Package (SOP) Tape & Reel
FAN6754MLMY
For Fairchild’s definition of Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html.