Features and Benefits
- High Efficiency: 90% Typical Over Entire Li-Ion Battery Range
- Wide VIN Range: 2.7V to 5.5V
- Up to 500mA Continuous Output Current
- Internal Soft-Start
- Open/Shorted LED Protection
- LED Current Matching Typically <2%
- Constant Frequency 1MHz Operation
- Low Shutdown Current: 6µA
- Overtemperature Protection
- Small Thermally Enhanced 16-Lead (4mm x 4mm) QFN Package
The LTC3453 is a synchronous buck-boost DC/DC converter optimized for driving up to 4 white LEDs at a combined current of up to 500mA from a single Li-Ion battery input. The regulator operates in either synchronous buck, synchronous boost, or buck-boost mode, depending on input voltage and LED maximum forward voltage. Optimum efficiency is achieved using a proprietary architecture that determines which LED requires the largest forward voltage drop at its programmed current, and regulates the common output rail for lowest dropout. Efficiency of 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 current setting resistors and dual enable pins. In shutdown, the supply current is only 6µA.
A high constant operating frequency of 1MHz allows the use of a small external inductor. The LTC3453 is offered in a low profile (0.75mm) thermally enhanced 16-lead (4mm x 4mm) QFN package.
- Cell Phones
- Digital Cameras
- Portable Devices
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 810 is a high efficiency buck-boost flash LED driver featuring the LTC3453 and the LXCL-PWF1 Lumileds Luxeon Flash LED. The board is optimized for 500mA (300ms) LED flash current or 150mA constant LED torch current with a single Lithium-Ion battery input voltage range of 2.7V to 4.2V or three AAA batteries in series. The Lithium-Ion battery input voltage range, high LED flash current and separate torch mode current setting, internal synchronous power switches, minimal and low-profile external components, and simple design makes the LTC3453 a great solution for highly efficient, space-constrained cellular telephone camera flash solutions. DC810 comes with three AAA batteries in series to simulate the capabilities of a typical Lithium-Ion cellular telephone battery.
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.