MP2109
Dual 1.2MHz, 800mA Synchronous
Step-Down Converter
MP2109 Rev.1.3 www.MonolithicPower.com 1
2/21/2006 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2006 MPS. All Rights Reserved.
The Future of Analog IC Technology
TM
TM
DESCRIPTION
The MP2109 contains two independent 1.2MHz
constant frequency, current mode, PWM
step-down converters. Each converter
integrates a main switch and a synchronous
rectifier for high efficiency without an external
Schottky diode. The MP2109 is ideal for
powering portable equipment that runs from a
single cell Lithium-Ion (Li+) battery. Each
converter can supply 800mA of load current
from a 2.5V to 6V input voltage. The output
voltage can be regulated as low as 0.6V. The
MP2109 can also run at 100% duty cycle for
low dropout applications.
EVALUATION BOARD REFERENCE
Board Number Dimensions
EV2109DQ-00A 1.5”X x 1.0”Y x 0.5”Z
FEATURES
• Up to 95% Efficiency
• 1.2MHz Constant Switching Frequency
• 800mA Load Current on Each Channel
• 2.5V to 6V Input Voltage Range
• Output Voltage as Low as 0.6V
• 100% Duty Cycle in Dropout
• Current Mode Control
• Short Circuit Protection
• Thermal Fault Protection
• <0.1µA Shutdown Current
• Internally Compensated
• Space Saving 10-Pin QFN Package
APPLICATIONS
• Cellular and Smart Phones
• Microprocessors and DSP Core Supplies
• PDAs
• MP3 Players
• Digital Still and Video Cameras
• Portable Instruments
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
TYPICAL APPLICATION
MP2109
IN2IN1
38
4
9
GND2GND1
FB2
SW2
EN2
7
5
6
2
10
1
FB1
SW1
EN1
V
IN1/IN2
2.5V to 6V
OFF ONOFF ON
V
OUT2
1.2V
800mA
V
OUT1
1.8V
800mA
MP2109_S01
100
95
90
85
80
75
70
65
60
55
50
EFFICIENCY (
%
)
0 500 1000
LOAD CURRENT (mA)
MP2109_EC01
V
OUT
=3.3V
