Features and Benefits
- High Efficiency: >90% Typical in Torch Mode, >80% in Flash Mode
- Wide VIN Range: 2.7V to 5.5V
- Up to 1A Continuous Output Current
- 3.5% LED Current Programming Accuracy
- Internal Soft-Start
- Open/Shorted LED Protection
- Constant Frequency 1MHz Operation
- Zero Shutdown Current
- Overtemperature Protection
- Small Thermally Enhanced 10-Lead (3mm × 3mm) DFN Package
The LTC3454 is a synchronous buck-boost DC/DC converter optimized for driving a single high power LED at currents up to 1A from a single cell Li-Ion battery input. The regulator operates in either synchronous buck, synchronous boost, or buck-boost mode depending on input voltage and LED forward voltage. PLED/PIN efficiency greater than 90% can be achieved over the entire usable range of a Li-Ion battery (2.7V to 4.2V).
LED current is programmable to one of four levels, including shutdown, with dual external resistors and dual enable inputs. In shutdown no supply current is drawn.
A high constant operating frequency of 1MHz allows the use of small external components.
The LTC3454 is offered in a low profile (0.75mm) thermally enhanced 10-lead (3mm × 3mm) DFN package.
- Cell Phone Camera Flash
- Cell Phone Torch Lighting
- Digital Cameras
- Misc Li-Ion LED Drivers
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 875 is a high efficiency buck-boost flash LED driver featuring the LTC3454EDD. The board has two circuits optimized for different applications: a small footprint solution featuring 350mA, 300ms LED flash current or 150mA constant LED torch current, and a high current solution featuring 400/600/1000mA constant-current operation. The input voltage range of 2.7V to 5.5V is suitable for a single Lithium-Ion battery or three AAA batteries in series. The Li-Ion input range, high LED flash current with separate torch mode current setting, internal synchronous power switches, minimal and low-profile external components, and simple design makes the LTC3454 the top solution for highly efficient, space-constrained cellular telephone camera flash solutions.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.