MP2105
1MHz, 800mA Synchronous
Step-Down Converter
MP2105 Rev. 1.2 www.MonolithicPower.com 1
8/19/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2005 MPS. All Rights Reserved.
The Future of Analog IC Technology
TM
TM
DESCRIPTION
The MP2105 is a 1MHz constant frequency,
current mode, PWM step-down converter. The
device integrates a main switch and a
synchronous rectifier for high efficiency without
an external Schottky diode. It is ideal for
powering portable equipment that runs from a
single cell Lithium-Ion (Li+) battery. The
MP2105 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 MP2105
can also run at 100% duty cycle for low dropout
applications.
The MP2105 is available in a low profile (1mm)
5-pin, TSOT package.
EVALUATION BOARD REFERENCE
Board Number Dimensions
EV2105DJ-00A 2.0”X x 2.0”Y x 0.5”Z
FEATURES
• High Efficiency: Up to 95%
• 1MHz Constant Switching Frequency
• 800mA Available Load Current
• 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
• Space Saving 5-Pin TSOT23 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
MP2105
SW
FB
3
5
EN
GND
2
IN
1
4
OUTPUT
1.8V
800mA
INPUT
2.5V to 6V
MP2105_TAC_S01
OFF ON
100
90
80
70
60
50
40
30
20
10
0
EFFICIENCY (%)
10 100 1000
LOAD CURRENT (mA)
MP2105-EC01
Efficiency vs
Load Current
V
IN
= 3.3V
V
IN
= 4.2V
