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LM3000_14 Datasheet, PDF (1/41 Pages) Texas Instruments – Dual Synchronous Emulated Current-Mode Controller
LM3000
www.ti.com
SNVS612A – JULY 2009 – REVISED JULY 2009
LM3000 Dual Synchronous Emulated Current-Mode Controller
Check for Samples: LM3000
FEATURES
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•2 VIN range from 3.3V to 18.5V
• Output voltage from 0.6V to 80% of VIN
• Remote differential output voltage sensing
• 1% accuracy at FB pin
• Interleaved operation reduces input capacitors
• Frequency sync/adjust from 200 kHz to 1.5
MHz
• Startup with pre-bias load
• Independent power good, enable, soft-start
and track
• Programmable current limit without external
sense resistor
• Hiccup mode short circuit protection
DESCRIPTION
The LM3000 is a dual output synchronous buck controller which is designed to convert input voltages ranging
from 3.3V to 18.5V down to output voltages as low as 0.6V. The two outputs switch at a constant programmable
frequency of 200 kHz to 1.5 MHz, with the second output 180 degrees out of phase from the first to minimize the
input filter requirements. The switching frequency can also be phase locked to an external frequency. A CLKOUT
provides an external clock 90 degrees out of phase with the main clock so that a second chip can be run out of
phase with the main chip. The emulated current-mode control utilizes bottom side FET sensing to provide fast
transient response and current limit without the need for external current sense resistors or RC networks.
Separate Enable, Soft-Start and Track pins allow each output to be controlled independently to provide maximum
flexibility in designing system power sequencing.
The LM3000 has a full range of protection features which include input under-voltage lock-out (UVLO), power
good (PGOOD) signals for each output, over-voltage crowbar and hiccup mode during short circuit events.
Applications
• DC Power Distribution Systems
• Graphic Cards - GPU and Memory ICs
• FPGA, CPLD, and ASICs
• Embedded Processor
• 1.8V and 2.5V I/O Supplies
• Networking Equipment (Routers, Hubs)
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
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 © 2009, Texas Instruments Incorporated