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LM3102 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – SIMPLE SWITCHER® Synchronous 1MHz 2.5A Step-Down Voltage Regulator
September 2007
LM3102
SIMPLE SWITCHER® Synchronous 1MHz 2.5A
Step-Down Voltage Regulator
General Description
The LM3102 Synchronously Rectified Buck Converter fea-
tures all required functions to implement a highly efficient and
cost effective buck regulator. It is capable of supplying 2.5A
to loads with an output voltage as low as 0.8V. Dual N-Chan-
nel synchronous MOSFET switches allow a low component
count, thus reducing complexity and minimizing board size.
Different from most other COT regulators, the LM3102 does
not rely on output capacitor ESR for stability, and is designed
to work exceptionally well with ceramic and other very low
ESR output capacitors. It requires no loop compensation, re-
sults in a fast load transient response and simple circuit
implementation. The operating frequency remains nearly con-
stant with line variations due to the inverse relationship be-
tween the input voltage and the on-time. The operating
frequency can be externally programmed up to 1 MHz. Pro-
tection features include VCC under-voltage lock-out, output
over-voltage protection, thermal shutdown, and gate drive
under-voltage lock-out. The LM3102 is available in the ther-
mally enhanced eTSSOP-20 package.
Key Specifications
■ Input voltage range 4.5V-42V
■ 2.5A output current
■ 0.8V, ±1.5% reference
■ Integrated dual N-Channel main and synchronous
MOSFETs
■ Thermally enhanced eTSSOP-20 package
Features
■ Low component count and small solution size
■ Stable with ceramic and other low ESR capacitors
■ No loop compensation required
■ High efficiency at a light load by DCM operation
■ Pre-bias startup
■ Ultra-fast transient response
■ Programmable soft-start
■ Programmable switching frequency up to 1 MHz
■ Valley current limit
■ Output over-voltage protection
■ Precision internal reference for an adjustable output
voltage down to 0.8V
■ Thermal shutdown
Typical Applications
■ 5VDC, 12VDC, 24VDC, 12VAC, and 24VAC systems
■ Embedded Systems
■ Industrial Control
■ Automotive Telematics and Body Electronics
■ Point of Load Regulators
■ Storage Systems
■ Broadband Infrastructure
■ Direct Conversion from 2/3/4 Cell Lithium Batteries
Systems
Typical Application
SIMPLE SWITCHER® is a registered trademark of National Semiconductor Corporation
© 2007 National Semiconductor Corporation 300213
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