LM3407 Datasheet, PDF (1/22 Pages) National Semiconductor (TI) – 350 mA, Constant Current Output Floating Buck Switching Converter for High Power LEDs

LM3407
www.ti.com
SNVS553B – JANUARY 2008 – REVISED MAY 2013
350 mA, Constant Current Output Floating Buck Switching Converter for High Power
LEDs
Check for Samples: LM3407
FEATURES
1
•2 Input operating range 4.5V to 30V
• Output voltage range: 0.1V_IN to 0.9V_IN
• Accurate constant current output
• Independent device enable (CMOS compatible)
and PWM dimming control
• Converter switching frequency adjustable from
300 kHz to 1 MHz
• No external control loop compensation
required
• Supports ceramic and low ESR output
capacitors
• Input Under Voltage Lock Out (UVLO)
• Thermal shutdown protection
• MSOP-8 PowerPAD Package
APPLICATIONS
• LED Driver
• Constant Current Source
• Automotive Lighting
• General Illumination
• Industrial Lighting
DESCRIPTION
The LM3407 is a constant current output floating
buck switching converter designed to provide
constant current to high power LEDs. The device is
ideal for automotive, industrial and general lighting
applications. The LM3407 has an integrated power N-
MOSFET that makes the application solution compact
and simple to implement. An external 1% thick-film
resistor allows the converter output voltage to adjust
as needed to deliver constant current within 10%
accuracy to a serially connected LED string of varying
number and type. Converter switching frequency is
adjustable from 300 kHz to 1 MHz. The LM3407
features a dimming input to enable LED brightness
control by Pulse Width Modulation (PWM).
Additionally, a separate enable pin allows for low
power shutdown. An exposed pad MSOP-8
PowerPAD package provides excellent heat
dissipation and thermal performance. Input UVLO
and output open-circuit protection ensure a robust
LED driver solution.
TYPICAL APPLICATION
1
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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.
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