LM3502   
Step-Up Converter for White LED Applications from the PowerWise® Family		 Click link to Download

Features
•Drive up to 4, 6, 8 or 10 white LEDs for Dual Display Backlighting
•>80% efficiency
•Output Voltage Options: 16V , 25V , 35V, and 44V
•Input Under-Voltage Protection
•Internal Soft Start Eliminating Inrush Current
•1 MHz Constant Switching Frequency
•Wide Input Voltage: 2.5V to 5.5V
•Small External Components
•Low Profile Packages: <1 mm Height -10 Bump MicroSMD -16 Pin LLP

Description

The LM3502 is a white LED driver for lighting applications. For dual display or large single white LED string backlighting applications, the LM3502 provides a complete solution. The LM3502 contains two internal white LED current bypass FET(Field Effect Transitor) switches that are ideal for controlling dual display applications. The white LED current can be adjusted with a PWM signal directly from a microcontroller without the need of an RC filter network.

With no external compensation, cycle-by-cycle current limit, over-voltage protection, and under-voltage protection, the LM3502 offers superior performance over other application specific standard product step-up white LED drivers.

Applications
•Dual Display Backlighting in Portable Devices
•Cellular Phones and PDAs



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Typical Application
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Block Diagram
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Typical Performance
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ParametersValues
Regulated LEDs 10
Boost Type Inductive
Switching Frequency 1000 kHz
Efficiency (peak) 80 %
Input Min Voltage 2.5 Volt
Input Max Voltage 5.5 Volt
OutputMax Voltage 35, 16, 44, 25 Volt
Special Features Dual display control
PWM BrightCtrl No
Analog-V BrightCtrl No
Ambient Light Compensation No
RGB-LED No
Temperature Min -40 deg C
Temperature Max 125 deg C
RegType Switching Regulator
PowerWise Yes

Datasheets
TitleSizeDateOther
Language
LM3502 Step-Up Converter for White LED Applications928
Kbytes		30-Aug-06 


Featured Application Notes
TitleSizeDateOther
Language
AN-1407: Application Note 1407 AN-1407 LM3502/03 Evaluation Board519
Kbytes		18-Jul-06 中文


More Application Notes
TitleSizeDateOther
Language
AN-1593: Application Note 1593 LM3508 Evaluation Board612
Kbytes		5-Jun-07 
AN-1594: Application Note 1594 LM3509 Evaluation Board1020
Kbytes		5-Jun-07 
AN-1309: Application Note 1309 LM3500 Evaluation Board35
Kbytes		12-Feb-04 
AN-1318: Application Note 1318 LM3501 Evaluation Board36
Kbytes		12-Feb-04 

Part Number(s)
(NSID)		Top ViewAvailabilityCurrent Reported StockBudgetary PricingStandard Pack Size
LM3502ITL-16/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide1239
FARNELLEurope and Asia50
NEWARKAmericas250
$2.10 each at 1K+ pcsreel
of
250
LM3502ITL-25/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide247
FARNELLEurope and Asia50
NEWARKAmericas240
RS COMPONENTSWorldwide145
$2.10 each at 1K+ pcsreel
of
250
LM3502ITL-35/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
FARNELLEurope and Asia247
NEWARKAmericas250
$2.10 each at 1K+ pcsreel
of
250
LM3502ITL-44/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide0
FARNELLEurope and Asia50
NEWARKAmericas238
RS COMPONENTSWorldwide1250
$2.10 each at 1K+ pcsreel
of
250
LM3502ITLX-16/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
3000
LM3502ITLX-25/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
3000
LM3502ITLX-35/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
3000
LM3502ITLX-44/NOPB

RoHS Status



MICRO SMD		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
3000
LM3502SQ-16/NOPB
LM3502SQ-16

RoHS Status



LLP		Full production
Lead Time: 6 weeks

Samples
DistributorRegionQty
ARROWWorldwide1000
DIGIKEYWorldwide1661
FARNELLEurope and Asia48
NEWARKAmericas1000
$2.10 each at 1K+ pcsreel
of
1000
LM3502SQ-25/NOPB
LM3502SQ-25

RoHS Status



LLP		Full production
Lead Time: 6 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide3957
FARNELLEurope and Asia49
NEWARKAmericas1000
$2.10 each at 1K+ pcsreel
of
1000
LM3502SQ-35/NOPB
LM3502SQ-35

RoHS Status



LLP		Full production
Lead Time: 6 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide2340
FARNELLEurope and Asia50
NEWARKAmericas1000
$2.10 each at 1K+ pcsreel
of
1000
LM3502SQ-44/NOPB
LM3502SQ-44

RoHS Status



LLP		Full production
Lead Time: 6 weeks

Samples
DistributorRegionQty
DIGIKEYWorldwide1996
FARNELLEurope and Asia35
NEWARKAmericas1000
$2.10 each at 1K+ pcsreel
of
1000
LM3502SQX-16/NOPB
LM3502SQX-16

RoHS Status



LLP		Full production
Lead Time: 6 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
4500
LM3502SQX-25/NOPB
LM3502SQX-25

RoHS Status



LLP		Full production
Lead Time: 6 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
4500
LM3502SQX-35/NOPB
LM3502SQX-35

RoHS Status



LLP		Full production
Lead Time: 6 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
4500
LM3502SQX-44/NOPB
LM3502SQX-44

RoHS Status



LLP		Full production
Lead Time: 12 weeks

 
DistributorRegionQty
DIGIKEYWorldwide0
$2.10 each at 1K+ pcsreel
of
4500

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/packaging/leadfree.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/quality/green.

National's certificate of product compliance is located at RoHS Status.

Part Number(s)
(NSID)		DescriptionAvailabilityCurrent Reported StockBudgetary PricingStandard Pack Size
LM3502ITL-44EV
Step-Up Converter for White LED ApplicationsFull production


 
DistributorRegionQty
DIGIKEYWorldwide5
NATIONALWorldwide15
$95.00 each1

Description:

The LM3502 is a white LED driver for lighting applications. For dual display or large single white LED string backlighting applications, the LM3502 provides a complete solution. The LM3502 contains two internal white LED current bypass FET (Field Effect Transistor) switches that are ideal for controlling dual display applications. The white LED current can be adjusted with a PWM signal directly from a microcontroller without the need of an RC filter network.

With no external compensation, cycle-by-cycle current limit, over-voltage protection, and under-voltage protection, the LM3502 offers superior performance over other application specific standard product step-up white LED drivers. step-up white LED drivers.

The LM3502/03 evaluation board is a working demonstration of a step up DC-DC converter. The LM3502/03 can drive up to 10 white LEDs. For evaluation purposes, the evaluation board is assembled in a micro SMD package for the 25V version (LM3503ITL) and the 44V version (LM3502ITL). The LM3502/03 are also available in a 16-LLP package (see ordering information). For further information on boost converter topology, device electrical characteristics, and component selection, please refer to the the LM3502 and LM3503 datasheets.

Features:

  • Drives up to 4, 6, 8, or 10 White LEDs for Dual Display Backlighting
  • >80% Peak Efficiency
  • Output Voltage Protection Options: 16V, 25V, 35V, and 44V
  • Input Under-Voltage Protection
  • Internal Soft Start Eliminates Inrush Current
  • 1 MHz Constant-Switching Frequency
  • Wide Input Voltage: 2.5V to 5.5V
  • Small External Components
  • Low Profile Packages: <1 mm Height
        ---10 Bump MicroSMD
        ---16 Pin LLP

Applications:

  • Dual-Display Backlighting in Portable devices
  • Cellular Phones and PDAs

Part Number(s)
(NSID)		Top ViewTypePinsMSL RatingPeak ReflowRoHS
Status		CAD SymbolsModelsPackage
Marking
Format
LM3502ITL-16/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SANB
LM3502ITL-25/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SAPB
LM3502ITL-35/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SARB
LM3502ITL-44/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SDLB
LM3502ITLX-16/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SANB
LM3502ITLX-25/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SAPB
LM3502ITLX-35/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SARB
LM3502ITLX-44/NOPB
MICRO SMD101260DetailDownloadN/A
XYTT
I SDLB
LM3502SQ-16/NOPB
LM3502SQ-16
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00048B
LM3502SQ-25/NOPB
LM3502SQ-25
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00049B
LM3502SQ-35/NOPB
LM3502SQ-35
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00044B
LM3502SQ-44/NOPB
LM3502SQ-44
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00050B
LM3502SQX-16/NOPB
LM3502SQX-16
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00048B
LM3502SQX-25/NOPB
LM3502SQX-25
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00049B
LM3502SQX-35/NOPB
LM3502SQX-35
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00044B
LM3502SQX-44/NOPB
LM3502SQX-44
LLP161
1		260
260		DetailDownloadN/A
NS
UZXYTT
L00050B

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/packaging/leadfree.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/quality/green.

National's certificate of product compliance is located at RoHS Status.

CAD Symbols and Models
Download LM3502 CAD Symbols
 Models
N/A

Reliability Metrics
Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
LM3502ITL-16ABCD15003417500423400011201409060
LM3502ITL-25ABCD15003417500423400011201409060
LM3502ITL-35ABCD15003417500423400011201409060
LM3502ITL-44ABCD15003417500423400011201409060
LM3502ITLX-16ABCD15003417500423400011201409060
LM3502ITLX-25ABCD15003417500423400011201409060
LM3502ITLX-35ABCD15003417500423400011201409060
LM3502ITLX-44ABCD15003417500423400011201409060
LM3502SQ-16ABCD15003417500423400011201409060
LM3502SQ-25ABCD15003417500423400011201409060
LM3502SQ-35ABCD15003417500423400011201409060
LM3502SQ-44ABCD15003417500423400011201409060
LM3502SQX-16ABCD15003417500423400011201409060
LM3502SQX-25ABCD15003417500423400011201409060
LM3502SQX-35ABCD15003417500423400011201409060
LM3502SQX-44ABCD15003417500423400011201409060

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.

For more information on Reliability Metrics, please click here.


All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/packaging/leadfree.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/quality/green.

National's certificate of product compliance is located at RoHS Status.

[Information as of 9-Feb-2010]