LM27965 - Dual Display White LED Driver with I2C Compatible Brightness Control from the PowerWise® Family
Datasheet Packaging Samples & Pricing Eval. Boards Reliability Application Notes Knowledge Base

Features
•91% Peak LED Drive Efficiency
•No Inductor Required
•0.3% Current Matching
•Drives LEDs with up to 30mA per LED
•180mA of total drive current
•I 2C Compatible Brightness Control Interface
•Adaptive 1× - 3/2× Charge Pump
•Resistor-Programmable Current Settings
•External Chip ^RESET Pin
•Extended Li-Ion Input: 2.7V to 5.5V
•Small low profile industry standard leadless package, LLP 24 : (4mm x 4mm x 0.8mm)
•25mm 2 total solution size
•Two I 2C Compatible Chip Address Options: 0x36 for LM27965SQ and 0x38 for LM27965SQ-M

General Description

The LM27965 is a highly integrated charge-pump-based dual-display LED driver. More...


Applications

•Mobile Phone Display Lighting
•PDA Backlighting
•General LED Lighting
  Typical Application
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ParametersValues
Regulated LEDs 9
Total LED Current 180 mA
Current Matching 0.3%
Boost Type Switched Capacitor Multi-Gain
Switching Frequency 1270 kHz
Efficiency (peak) 91 %
Input Min Voltage 2.7 Volt
Input Max Voltage 5.5 Volt
Boost Voltage Regulated
LED Configuration Parallel
Supply Current 2.9 mA
Switching Type Fixed Freq
Special Features Current regulated outputs, Common anode current sink topology, I2C compatible interface
PWM BrightCtrl Yes
Analog-V BrightCtrl Yes
Ambient Light Compensation No
RGB-LED No
Temperature Min -30 deg C
Temperature Max +85 deg C
RegType WhiteLED Driver
PowerWise Yes


Typical Performance

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  Additional Resources
Application Notes


Block Diagram

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Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM27965 Dual Display White LED Driver with I2C Compatible Brightness Control 356
Kbytes		 23-Oct-07 Download
LM27965 Dual Display White LED Driver with I2C Compatible Brightness Control (Japanese)
 530 Kbytes   Download

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Package Availability, Models, Samples & Pricing
Part NumberPackageFactory Lead TimeModelsSamples &
Electronic
Orders		Budgetary PricingStd
Pack
Size		Package
Marking
Format
TypePinsSpec.MSL
Rating		Peak
Reflow		RoHS
Report		CAD
Symbols		WeeksQtyQty$US each
LM27965SQEVDual Display White LED Driver with I2C Compatible Brightness ControlFull productionN/A
 
Buy Now 		1+$121.001-
6 weeksN/A
LM27965SQ-MLLP24NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$1.43reel
of
1000		NS
UZXYTT
27965M
6 weeksN/A
LM27965SQLLP24NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$1.43reel
of
1000		NS
UZXYTT
L27965S
12 weeks2000
LM27965SQX-MLLP24NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$1.43reel
of
4500		NS
UZXYTT
27965M
12 weeksN/A
LM27965SQXLLP24NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$1.43reel
of
4500		NS
UZXYTT
L27965S
6 weeks25000

General Description

The LM27965 is a highly integrated charge-pump-based dual-display LED driver. The device can drive up to 9 LEDs in parallel with a total output current of 180mA. Regulated internal current sinks deliver excellent current and brightness matching in all LEDs.

The LED driver current sinks are split into three independently controlled groups. The primary group can beconfigurabled with 4 or 5 LEDs, for backlighting a larger main display and the second group can be configured with 2 or 3 LEDs, for backlighing a smaller secondary display. An additional, independently controlled led driver is provided for driving an indicator or general purpose LED. The LM27965 has an I 2C compatible interface that allows the user to independently control the brightness on each bank of LEDs.

The device provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2, or in Pass-Mode. The proper gain for maintaining current regulation is chosen based on LED forward voltage, so that efficiency is maximized over the input voltage range.

The LM27965 is available in National's small 24-pin Leadless Leadframe Package (LLP-24).

Reliability Metrics

Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
LM27965SQCMOS70184060010890004309006723
LM27965SQ-MCMOS70184060010890004309006723
LM27965SQXCMOS70184060010890004309006723
LM27965SQX-MCMOS70184060010890004309006723

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.


Application Notes

TitleSize in Kbytes Date Click link below to Download
AN-1582: Application Note 1582 LM27965 Dual Display White LED Driver with I2C Compatible Brightness Control 1226
Kbytes		 18-Mar-07 Download
AN-1582 (Chinese): Application Note 1582 LM27965 Dual Display White LED Driver with I2C Compatible Brightness Control
 503 Kbytes  

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More Application Notes

TitleSize in Kbytes Date Click link below to Download
AN-1321: Application Note 1321 LM2796 Evaluation Board 453
Kbytes		 25-May-04 Download
AN-1362: Application Note 1362 LM27961- Dual-Display White LED Driver with 3/2x Switched Capacitor Boost 625
Kbytes		 30-Jun-05 Download
AN-1362 (Chinese): Application Note 1362 LM27961- Dual-Display White LED Driver with 3/2x Switched Capacitor Boost
 276 Kbytes  

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[Information as of 7-Nov-2009]