LM3402/LM3402HV 0.5A Constant Current Buck Regulator for Driving High Power LEDs
June 2007
LM3402/LM3402HV
0.5A Constant Current Buck Regulator for Driving High
Power LEDs
General Description
The LM3402/02HV are monolithic switching regulators de-
signed to deliver constant currents to high power LEDs. Ideal
for automotive, industrial, and general lighting applications,
they contain a high-side N-channel MOSFET switch with a
current limit of 735 mA (typical) for step-down (Buck) regula-
tors. Hysteretic control with controlled on-time coupled with
an external resistor allow the converter output voltage to ad-
just as needed to deliver a constant current to series and
series - parallel connected arrays of LEDs of varying number
and type, LED dimming by pulse width modulation (PWM),
broken/open LED protection, low-power shutdown and ther-
mal shutdown complete the feature set.
Features
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Integrated 0.5A N-channel MOSFET
V
IN
Range from 6V to 42V (LM3402)
V
IN
Range from 6V to 75V (LM3402HV)
500 mA Output Current Over Temperature
Cycle-by-Cycle Current Limit
No Control Loop Compensation Required
Separate PWM Dimming and Low Power Shutdown
Supports all-ceramic output capacitors and capacitor-less
outputs
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Thermal shutdown protection
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MSOP-8, PSOP-8 Packages
Applications
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LED Driver
Constant Current Source
Automotive Lighting
General Illumination
Industrial Lighting
Typical Application
20192101
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201921
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