CM3718
1.5A L
OW
-N
OISE
PWM S
TEP
-D
OWN
R
EGULATOR
GENERAL DESCRIPTION
The CM3718 is a low-noise, pulse-width-modulated (PWM),
DC-DC step-down converter. It powers logic and transmitters
in small wireless systems such as cellular phones,
communicating PDAs, and handy-terminals. The device
features an internal synchronous rectifier for high efficiency; it
requires no external Schottky diode. Excellent noise
characteristics and fixed-frequency operation provide easy
post-filtering. The CM3718 is ideally suited for Li-lon battery
applications. It is also useful for +3V or +5V fixed input
applications.
The device operates in one of four modes. Forced PWM
mode operates at a fixed frequency regardless of the load.
Shutdown mode places the device in standby, reducing
quiescent supply current to under 0.1μA.
The CM3718 can deliver over 1.5A. The output voltage can be
adjusted from VREF to VIN. The input range is from 2.0V to
5.0V. Other features of the CM3718 include high efficiency,
low dropout voltage. It is available in a space-saving 8-pin
SOP package.
FEATURES
Patent Number #6,452,366
1.2MHz switching and synchronization
Dynamic output-voltage adjustment from VREF to VIN
1.5A Guaranteed Output Current
95% Efficiency
No Schottky Diode Required
External Soft Start
8-pin PSOP power packages
APPLICATIONS
Cellular Phone
Cordless Phone
PDAs and Handy-Terminals
CPU I/O Supplies
Notebook Chipset Supplies
Battery Operated Devices
PIN CONFIGURATION
PSOP-8 (PT-08)
Top View
1
2
3
4
VIN
GND
SD
VREF
PVIN
LX
PGND
VFB
8
7
6
5
2006/10/11
Rev. 1.6
Champion Microelectronic Corporation
Page 1
CHAMP [ CHAMPION MICROELECTRONIC CORP. ]
