LM3100_14 Datasheet, PDF (1/21 Pages) Texas Instruments – SIMPLE SWITCHER® Synchronous 1MHz 1.5A Step-Down Voltage Regulator

LM3100
www.ti.com
SNVS421F – JANUARY 2006 – REVISED DECEMBER 2009
LM3100 SIMPLE SWITCHER® Synchronous 1MHz 1.5A Step-Down Voltage Regulator
Check for Samples: LM3100
FEATURES
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•2 Input voltage range 4.5V - 36V
• 1.5A output current
• 0.8V, ±1.5% reference
• Integrated 40V, dual N-Channel buck
synchronous switches
• Low component count and small solution size
• No loop compensation required
• Ultra-fast transient response
• Stable with ceramic and other low ESR
capacitors
• Programmable switching frequency up to
1MHz
• Max. duty cycle limited during start-up
• Valley current limit
• Precision Internal Reference for adjustable
output voltage down to 0.8V
• Thermal shutdown
• Thermally enhanced eTSSOP-20 package
TYPICAL APPLICATIONS
• 5VDC, 12VDC, 24VDC, 12VAC, and 24VAC
systems
• Embedded Systems
• Industrial Controls
• Automotive Telematics and Body Electronics
• Point of Load Regulators
• Storage Systems
• Broadband Infrastructure
• Direct Conversion from 2/3/4 Cell Lithium
Batteries Systems
DESCRIPTION
The LM3100 Synchronously Rectified Buck Converter features all functions needed to implement a highly
efficient, cost effective buck regulator capable of supplying 1.5A to loads with voltages as low as 0.8V. Dual 40V
N-Channel synchronous MOSFET switches allow for low external component thus reducing complexity and
minimizing board space. The LM3100 is designed to work exceptionally well with ceramic and other very low
ESR output capacitors. The Constant ON-Time (COT) regulation scheme requires no loop compensation, results
in fast load transient response, and simplifies circuit implementation. Through the use of a unique design the
regulator does not rely on output capacitor ESR for stability, as do most other COT regulators. The operating
frequency remains nearly constant with line and load variations due to the inverse relationship between the input
voltage and the on-time. The oprating frequency can be externally programmed up to 1MHz. Protection features
include V_CC under-voltage lockout, thermal shutdown and gate drive under-voltage lockout. The part is available
in a thermally enhanced eTSSOP-20 package
Typical Application
V_IN
C_IN
C_BST
C_SS
L
N/C
SW
SW
VIN
VIN
BST
GND
SS
N/C
N/C
N/C
N/C
PGND
PGND
VCC
RON
EN
FB
N/C
TST
R_ON
C_FB
R_EN
R_FB1
R_FB2
C_VCC
V_OUT
C_OUT
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2006–2009, Texas Instruments Incorporated