LM3409_10 Datasheet, PDF (1/30 Pages) National Semiconductor (TI) – PFET Buck Controller for High Power LED Drives

LM3409 / LM3409HV
LM3409Q / LM3409QHV
April 12, 2010
PFET Buck Controller for High Power LED Drives
General Description
The LM3409/09HV are P-channel MosFET (PFET) con-
trollers for step-down (buck) current regulators. They offer
wide input voltage range, high-side differential current sense
with low adjustable threshold voltage, fast output enable/dis-
able function and a thermally enhanced eMSOP-10 package.
These features combine to make the LM3409/09HV ideal for
use as constant current sources for driving LEDs where for-
ward currents up to 5A are easily achievable. The
LM3409/09Q/09HV/09QHV uses Constant Off-Time (COFT)
control to regulate an accurate constant current without the
need for external control loop compensation. Analog and
PWM dimming are easy to implement and result in a highly
linear dimming range with excellent achievable contrast ra-
tios. Programmable UVLO, low-power shutdown, and thermal
shutdown complete the feature set.
Features
■ ^{LM3409Q/LM3409QHV is an Automotive Grade product}
that is AEC-Q100 grade 1 qualified
■ 2Ω, 1A Peak MosFET Gate Drive
■ ^V_IN ^{Range: 6V to 42V (LM3409/LM3409Q)}
■ ^V_IN ^{Range: 6V to 75V (LM3409HV/LM3409QHV)}
■ ^{Differential, High-side Current Sense}
■ ^{Cycle-by-Cycle Current Limit}
■ ^{No Control Loop Compensation Required}
■ ^{10,000:1 PWM Dimming Range}
■ ^{250:1 Analog Dimming Range}
■ ^{Supports All-Ceramic Output Capacitors and Capacitor-}
less Outputs
■ ^{Low Power Shutdown}
■ ^{Thermal Shutdown Protection}
■ ^{Thermally Enhanced eMSOP-10 Package}
Applications
■ ^{LED Driver}
■ ^{Constant Current Source}
■ ^{Automotive Lighting}
■ ^{General Illumination}
■ ^{Industrial Lighting}
Typical Application
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