Texas Instruments LM3644
The LM3644 is a dual LED flash driver that provides a high level of adjustability within a small solution size. The LM3644 utilizes a 2-MHz or 4-MHz fixedfrequency synchronous boost converter to provide power to the dual 1.5-A constant current LED sources. The dual 128 level current sources provide the flexibility to adjust the current ratios between LED1 and LED2.| Part No. | LM3644 |
|---|---|
| Datasheet | LM3644 Download |
| Manufacturer |  Texas Instruments |
| Description | Dual 1.5-A Current Source Camera Flash LED Driver |
| Buy | Stock & Price |
FEATURES
●1 Dual Independent 1.5-A LED Current Source Programmability● Accurate and Programmable LED Current Range from 1.4 mA to 1.5 A
● Torch Currents up to 360 mA (LM3644TT)
● Flash Timeout Values up to 1.6 seconds (LM3644TT)
● Optimized Flash LED Current During Low Battery Conditions (IVFM)
● > 85% Efficiency in Torch Mode (at 100 mA) and Flash Mode (at 1 A to 1.5 A)
● Grounded Cathode LED Operation for Improved Thermal Management
● Small Solution Size: < 16 mm2
● Hardware Strobe Enable (STROBE)
● Synchronization Input for RF Power Amplifier Pulse Events (TX)
● Hardware Torch Enable (TORCH/TEMP)
● Remote NTC Monitoring (TORCH/TEMP)
● 400-kHz I2C-Compatible Interface – LM3644 (I2C Address = 0x63) 2
APPLICATIONS
● Camera Phone White LED Flash● Digital Still Cameras
● Fire-Alarm Notification
● Emergency Strobe Lighting
● Intruder Alert Notification
● Barcode Scanners
● Handheld Data Terminals 3
DESCRIPTION
An adaptive regulation method ensures the current sources remain in regulation and maximizes efficiency.
