MP2351
1.5A, 23V, 1.4MHz
Step-Down Converter
MP2351 Rev. 1.5 www.MonolithicPower.com 1
1/6/2006 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2006 MPS. All Rights Reserved.
The Future of Analog IC Technology
TM
TM
DESCRIPTION
The MP2351 is a monolithic step down switch
mode converter with a built in internal power
MOSFET. It achieves 1.5A continuous output
current over a wide input supply range with
excellent load and line regulation.
Current mode operation provides fast transient
response and eases loop stabilization.
Fault condition protection includes cycle-by-cycle
current limiting, short circuit frequency foldback
and thermal shutdown. In shutdown mode the
regulator draws 20µA of supply current.
The MP2351 requires a minimum number of
readily available standard external components.
EVALUATION BOARD REFERENCE
Board Number Dimensions
EV2351DQ-00A 2.3”X x 1.5”Y x 0.5”Z
FEATURES
• 1.5A Output Current
• 0.18Ω Internal Power MOSFET Switch
• Stable with Low ESR Output Ceramic
Capacitors
• Up to 93% Efficiency
• 20µA Shutdown Mode
• Fixed 1.4MHz Frequency
• Thermal Shutdown
• Cycle-by-Cycle Over Current Protection
• Wide 4.75V to 23V Operating Input Range
• Output Adjustable from 1.23V to 16V
• Programmable Under Voltage Lockout
• Frequency Synchronization Input
• Available in QFN (3mm x 3mm) and tiny
10-Pin MSOP Packages
• Evaluation Board Available
APPLICATIONS
• Distributed Power Systems
• Battery Charger
• DSL Modems
• Pre-Regulator for Linear Regulators
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
TYPICAL APPLICATION
MP2351
SW
IN BS
4
2
5
7
86
10
9
FB
SYNC
COMPGND
EN
V
OUT
3.3V/1.5A
INPUT
4.75V - 23V
OPEN
NOT USED
OPEN
AUTOMATIC
STARTUP
MP2351_TAC_S01
C5
10nF
C3
1nF
C6
OPEN
D1
B220A
V
OUT
=5V
V
OUT
=2.5V
V
OUT
=3.3V
100
90
80
70
60
50
40
EFFICIENCY (%)
0 1500300 600 900 1200
LOAD CURRENT (mA)
MP2351-EC01
Efficiency vs
Load Current
