LM3433 - Common Anode Capable High Brightness LED Driver with High Frequency Dimming

	LM3433 - Common Anode Capable High Brightness LED Driver with High Frequency Dimming from the PowerWise® Family

Datasheet	Packaging	Samples & Pricing	Eval. Boards	Reliability	Application Notes	Knowledge Base

Features

•	Operating input voltage range of -9V to -14V w.r.t. LED anode
•	Control inputs are referenced to the LED anode
•	Output current greater than 6A
•	Greater than 30kHz PWM frequency capable
•	Negative output voltage capability allows LED anode to be tied directly to chassis for maximum heat sink efficacy
•	No output capacitor required
•	Up to 1MHz switching frequency
•	Low I_Q, 1mA typical
•	Soft start
•	Adaptive programmable ON time allows for constant ripple current
•	LLP-24 package

General Description

The LM3433 is an adaptive constant on-time DC/DC buck (step-down) constant current controller (a true current source). More...

Applications

•	LCD backlighting
•	Projection systems
•	Solid state lighting
•	Automotive lighting

Typical Application

click for larger image

Front page schematic

Parametric Table expand

Parametric Table collapse

Topology Buck

Input Min Voltage 9 Volt

Input Max Voltage 14 Volt

Output Range 0V to 6V

Output Current 30000 mA

Efficiency (peak) 92 %

Topology Buck

Input Min Voltage 9 Volt

Input Max Voltage 14 Volt

Output Range 0V to 6V

Output Current 30000 mA

Efficiency (peak) 92 %

Output Min 0 Volt

Output Max 6 Volt

Special Features Common anode capable for maximum heat efficacy, output current greater than 6A, high frequency PWM dimming

Adjustable Output Yes

On/Off Pin Yes

Error Flag No

Output Power 30 Watt

Switching Frequency 500 kHz

Adj Switch Frequency Yes

Sync Pin No

Step-Down Yes

Step-Up No

Inverting No

Flyback No

RegType Switching Controller

Temperature Min -40 deg C

Temperature Max 125 deg C

Feedback Voltage 0.06 Volt

PowerWise Yes

View Using Catalog

Typical Performance

click for larger image

Additional Resources

Application Notes (see below)

Block Diagram

click for larger image

Block diagram

Datasheet

RoHS Compliance Information	Size in Kbytes	Date
LM3433 Common Anode Capable High Brightness LED Driver with High Frequency Dimming	338 Kbytes	7-Mar-08	View Online Download

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Package Availability, Models, Samples & Pricing

Part Number

Package

Factory Lead Time

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking
Format

Type

Pins

Spec.

MSL
Rating

Peak
Reflow

RoHS
Report

CAD
Symbols

Weeks

Qty

$US each

LM3433EVALKIT

LM3433 Evaluation Kit with 3 Boards: LM3433, Dummy-Load, LED

Full production

N/A

$300.00

8 weeks

N/A

LM3433SQ-14AEV

LM3433 Eval Board with 14A Drive

Full production

N/A

$100.00

8 weeks

N/A

LM3433SQ

LLP

NOPB

260

RoHS

N/A

Full production

N/A

1K+

$2.50

reel
of
1000

NS
UZXYTT
L3433SQ

6 weeks

N/A

LM3433SQX

LLP

NOPB

260

RoHS

N/A

Full production

N/A

1K+

$2.50

reel
of
4500

NS
UZXYTT
L3433SQ

6 weeks

N/A

General Description

The LM3433 is an adaptive constant on-time DC/DC buck (step-down) constant current controller (a true current source). The LM3433 provides a constant current for illuminating high power LEDs. The output configuration allows the anodes of multiple LEDs to be tied directly to the ground referenced chassis for maximum heat sink efficacy. The high frequency capable architecture allows the use of small external passive components and no output capacitor while maintaining low LED ripple current. Two control inputs are used to modulate LED brightness. An analog current control input is provided so the LM3433 can be adjusted to compensate for LED manufacturing variations and/or color temperature correction. The other input is a logic level PWM control of LED current. The PWM functions by shorting out the LED with a parallel switch allowing high PWM dimming frequencies. High frequency PWM dimming allows digital color temperature control, interference blanking, field sequential illumination, and brightness control. Additional features include thermal shutdown, V_CC under-voltage lockout, and logic level shutdown mode. The LM3433 is available in a low profile LLP-24 package.

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM *	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM3433SQ	ABCD150	0	28280	0	0	2974000	2	843880620
LM3433SQX	ABCD150	0	28280	0	0	2974000	2	843880620

Note: The Early Failure Rates were calculated as point estimates. 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.

For more information on Reliability Metrics, please click here.

Application Notes

Title	Size in Kbytes	Date
AN-1736: Application Note 1736 LM3433 HB LED Driver Evaluation Kit	1011 Kbytes	4-Feb-08	Download
AN-1793: Application Note 1793 LM3433 4A to 20A LED Driver Evaluation Board	701 Kbytes	25-Aug-08	Download

If you have trouble printing or viewing PDF file(s), see Printing Problems.

More Application Notes

Title	Size in Kbytes	Date
AN-1679: Application Note 1679 LED Backlighting Solution with LM3430 and LM3432	2763 Kbytes	18-Sep-07	Download
AN-1764: Application Note 1764 LM3431 Evaluation Board	588 Kbytes	10-Jan-08	Download
AN-1529: Application Note 1529 LM3430 Evaluation Board	2770 Kbytes	21-Aug-07	Download
AN-1529 (Chinese): Application Note 1529 LM3430 Evaluation Board	789 Kbytes

If you have trouble printing or viewing PDF file(s), see Printing Problems.

[Information as of 20-Nov-2008]