C2471 Datasheet, PDF (1/18 Pages) List of Unclassifed Manufacturers – RDFC Controllers for Offline Applications up to 6 W

C2471 Datasheet
RDFC Controllers for Offline Applications up to 6 W
ADVANTAGES
 Low system component count
 High average efficiency
 Low no load power consumption
 EMI compliance without extra components
 High isolation & surge voltage withstand
 High power density in very small size
C2471LW1
PDIP-8
FEATURES
 Highly integrated CMOS controller IC
 Low cost package options
 Drive suitable for low cost bipolar power transistors
 Resonant switching for high efficiency and low EMI
 Frequency optimised for power circuit parasitics
 Protection against overload, over-temperature and under-voltage
C2471LX2
SOT23-6
APPLICATIONS
External AC/DC charger/adapter (single voltage input) e.g. cordless phones, low power adapters.
Embedded PSU (single voltage input), audio products, domestic appliances.
OVERVIEW
The C2471 controllers use CamSemi’s low power Resonant Discontinuous Forward Converter (RDFC)
topology to create a high efficiency, low cost alternative to line-frequency transformer PSUs, for applications
up to 6 W. By operating in resonant mode, EMI is greatly reduced, enabling the replacement of linear PSUs
in demanding applications such as audio products and cordless phone chargers. The C2471 controllers also
offer overload protection which is usually associated with more expensive switch mode solutions.
VDD
AUX
Vdd
COL
CS
Switch
saturation
sensing
Resonance
sensing
Current
sensing
Vdd
regulator
RDFC
Control
Base
drive
BAS
GND
Figure 1: Block Diagram of the C2471 Controller ICs
Product data
© Cambridge Semiconductor Ltd 2008
Page 1 of 18
DS-1639-0805
02-May-2008