Features • LM3424Q is an Automotive Grade product that is AEC-Q100 grade 1 qualified (-40°C to +125°C operating junction temperarure) • VIN range from 4.5V to 75V • High-side adjustable current sense • 2Ω, 1A Peak MosFET gate driver • Input under-voltage and output over-voltage protection • PWM and analog dimming • Cycle-by-cycle current limit • Programmable slope compensation • Programmable, synchronizable switching frequency • Programmable thermal foldback • Programmable softstart • Precision voltage reference • Low power shutdown and thermal shutdown Description The LM3424 is a versatile high voltage N-channel MosFET controller for LED drivers . It can be easily configured in buck, boost, buck-boost and SEPIC topologies. In addition, the LM3424 includes a thermal foldback feature for temperature management of the LEDs. This flexibility, along with an input voltage rating of 75V, makes the LM3424 ideal for illuminating LEDs in a large family of applications. Adjustable high-side current sense voltage allows for tight regulation of the LED current with the highest efficiency possible. The LM3424 uses standard peak current-mode control providing inherent input voltage feed-forward compensation for better noise immunity. It is designed to provide accurate thermal foldback with a programmable foldback breakpoint and slope. In addition, a 2.45V reference is provided. The LM3424 includes a high-voltage startup regulator that operates over a wide input range of 4.5V to 75V. The internal PWM controller is designed for adjustable switching frequencies of up to 2.0 MHz and external synchronization is possible. The controller is capable of high speed PWM dimming and analog dimming. Additional features include slope compensation, softstart, over-voltage and under-voltage lock-out, cycle-by-cycle current limit, and thermal shutdown. The LM3424Q is an Automotive Grade product that is AEC-Q100 grade 1 qualified. Applications • LED Drivers - Buck, Boost, Buck-Boost, and SEPIC • Indoor and Outdoor Area SSL • Automotive • General Illumination • Constant-Current Regulators

LM3424   4.50 <= V in Lower  V   <= V in Upper  V   <= 75.00 Ambient Temperature  °C <= 100 Thermal Foldback Support:   0 <= Start temp.  °C   <= Stop temp.  °C   <= 150 What are WEBENCH® tools? Design #2 schematic MY BRIEFCASE                                       Click any "Briefcase" icon to add an item

Typical Application click for larger image Design #2 schematic	Block Diagram click for larger image Block diagram
Typical Performance click for larger image Boost Efficiency Graph

Datasheet

Title		Size	Date	Other Language
	LM3424 Constant Current N-Channel Controller with Thermal Foldback for Driving LEDs	1362 Kbytes	15-Oct-09

Featured Application Notes

Title		Size	Date	Other Language
	AN-1969: Application Note 1969 LM3424 Boost Evaluation Board	988 Kbytes	22-Aug-09
	AN-1967: Application Note 1967 LM3424 Buck-Boost Evaluation Board	1027 Kbytes	22-Aug-09

More Application Notes

Title		Size	Date	Other Language
	AN-1982: Application Note 1982 Small, Wide Input Voltage Range LM2842 Keeps LEDs Cool	63 Kbytes	15-Jul-09
	AN-1907: Application Note 1907 LM3423 Buck-Boost Configuration Evaluation Board	879 Kbytes	8-Dec-08
	AN-1872: Application Note 1872 LM3423 Boost Evaluation Board	764 Kbytes	8-Dec-08
	AN-1985: Application Note 1985 LM3429 Buck-Boost Evaluation Board	705 Kbytes	3-Aug-09
	AN-1986: Application Note 1986 LM3429 Boost Evaluation Board	672 Kbytes	3-Aug-09

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM3424MH	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM3424MHX	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM3424QMH	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM3424QMHX	ABCD150XV1	0	3868	0	0	2595000	2	736338335

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

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