LM2759 - 1A Switched Capacitor Flash LED Driver with I2C Compatible Interface from the PowerWise® Family
Datasheet Packaging Samples & Pricing Reliability Application Notes Knowledge Base

Features
Up to 1A Output Current
Solution Area < 22 mm 2
No Inductor Required
90% Peak Efficiency
Adaptive 1x, 1.5x and 2x Gains for Maximum Efficiency
Load Disconnect in Shutdown
Accurate Input Current Control During Gain Transitions
Flash Time-Out
TX Input Pin Ensures Synchronization with RF Power Amplifier Pulse
Torch, Flash, and Indicator Modes
External Flash Enable via Strobe Input Pin
Strobe Input Disable via I 2C
Programmable Flash Pulse Duration, and Torch and Flash Currents via I 2C-Compatible Interface
1MHz Constant Frequency Operation
Low Profile 12–Pin LLP (3mm x 3mm x 0.8mm)

General Description


LM2759 is an integrated low-noise, high-current switched capacitor DC/DC converter with a regulated current source. More...


Applications


Camera Flash in Cellular Phones
  Typical Application
click for larger image

typ application circuit - simple

ParametersValues
Regulated LEDs 1
Total LED Current 1000 mA
Boost Type Switched Capacitor Multi-Gain
Switching Frequency 1000 kHz
Efficiency (peak) 90 %
Input Min Voltage 2.7 Volt
Input Max Voltage 5.5 Volt
LED Configuration Parallel
Current Matching Perfect
OutputMax Voltage 5.4 Volt
Switching Type Fixed Freq
Special Features Flash, Torch, I2C
Analog-V BrightCtrl No
Ambient Light Compensation No
RGB-LED No
Temperature Min -30 deg C
Temperature Max 85 deg C
RegType Switched Cap Regulator
PowerWise Yes

Additional Resources


Application Notes



Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM2759 PRODUCT BRIEF 1A Switched Capacitor Flash LED Driver with I 2 C Compatible Interface 115
Kbytes
20-Nov-08 Download

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


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
LM2759SDLLP12NOPB3260RoHS N/A Full productionN/A
 
Buy Now
1K+$0.80reel
of
1000
ZXYTT
L2759
6 weeksN/A
LM2759SDXLLP12NOPB3260RoHS N/A Full productionN/A
 
Buy Now
1K+$0.80reel
of
4500
ZXYTT
L2759
6 weeksN/A

General Description


LM2759 is an integrated low-noise, high-current switched capacitor DC/DC converter with a regulated current source. The device requires only four small ceramic capacitors making the total solution area less than 22 mm 2 and the height less than 1 mm. The LM2759 is capable of driving loads up to 1A from a single-cell Li-Ion battery. Maximum efficiency is achieved over the input voltage range by actively selecting the proper gain based on the LED forward voltage and current requirements.

The LED current can be programmed up to 1A via an I 2C-compatible interface, along with eight selectable Flash Time-Out durations. One high-current Flash LED can be driven either in a high-power Flash mode or a low-power Torch mode. The Strobe pin allows the flash to be toggled via a Flash enable signal from a camera module. The TX input pin limits the Flash LED current to the Torch current level during a RF PA pulse, to reduce high loads on the battery. Internal soft-start circuitry limits the amount of inrush current during start-up.

LM2759 is offered in a small 12-pin thermally enhanced LLP package.

Notice: This document is not a full datasheet. For more information regarding this product or to order samples, please contact your National Semiconductor sales office or visit http://www.national.com/support/dir.html.

Reliability Metrics


Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
LM2759SDCMOS70184060010890004309006723
LM2759SDXCMOS70184060010890004309006723

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.


More Application Notes


TitleSize in Kbytes Date Click link below to Download
AN-1998: Application Note 1998 How to Meet the HDMI 5V Source Requirement 117
Kbytes
28-Aug-09 Download
AN-1731: Application Note 1731 LM2757 Evaluation Board 573
Kbytes
19-Feb-08 Download

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

[Information as of 8-Nov-2009]