88EM8040/88EM8041
Power Factor Correction Controller for Flyback Topology
Datasheet
PRODUCT OVERVIEW
The Marvell
®
88EM8040/88EM8041 device is a high
performance Power Factor Correction (PFC) Controller for
flyback applications. Both devices work at fixed frequencies,
88EM8040 at 60kHz while 88EM8041 at 120kHz. It can be used
in a wide variety of universal input PFC flyback converters with
an output power range of up to 150W without using any external
driver.
Marvell advanced mixed signal technology ensures the lowest
Total Harmonic Distortion (THD) in the industry. The IC operates
under average Continuous Conduction Mode (CCM).
The 88EM8040/88EM8041 PFC controller improves the steady
state and transient performance through Marvell's innovative
Digital Signal Processing (DSP) solution. The proprietary
adaptive over-current protection has the ability to ensure almost
constant power constraint and provides safety provisions
including open loop and over voltage protection protocols.
The internal voltage loop compensation and current loop control
guarantees system stability and thus reduces the external
component count and costs.
The 8-pin SOIC package further facilitates the application
design process, saving board space. The resultant simple
system design and minimum cost makes 88EM8040/88EM8041
the ideal choice for any flyback application with PFC.
General Features
Patented DSP control with adaptive loop coefficient
Continuous Conduction Mode (CCM) operation
Average current mode control
Adaptive control loop achieves high power factor for a
wide range of voltage and load conditions
Adaptive over current protection for universal voltage
Fixed frequency of operation
High power factor and low harmonic distortion for a wide
range of load conditions
Up to 2A driver capability
Minimal external components required
Under voltage lockout (UVLO)
Over voltage protection (OVP)
Thermal shutdown
Input line frequency range from 45Hz to 65Hz
Applications
Universal input PFC flyback converters
AC/DC adaptors and battery charger
Figure 1: PFC Flyback Circuit Diagram
V
DCin
Bridge
Retifier
diode
C
in
PFC
C
sn
R
sn
D
sn
AC
IN
R
cs
R
a
R
b
R
c
C
cs
OCP SW SGND
R
S1
R
gate
R
sen
Drain
Q1
N
p
D
R2
V
out
N
S2
C
O2
Load
ISNS
VIN
VDD
88EM8040/
8041
FB
PGND
R
S4
C
S2
R
S2
C
S1
R
S5
Opto-Coupler
C
VDD
R
f1
V
ref
R
S3
Copyright © 2009 Marvell
October 5, 2009, Preliminary
Document Classification: Proprietary
Doc. No. MV-S104983-01 Rev. A
Page 3
MARVELL [ MARVELL TECHNOLOGY GROUP LTD. ]
