LTC3452 - Synchronous Buck-Boost MAIN/CAMERA White LED Driver
Features
- High Efficiency: ≥85% Over Entire Li-Ion Battery Range
- Wide VIN Range: 2.7V to 5.5V
- Independent MAIN/CAMERA Current Control
- Up to 425mA Continuous Output Current
- Internal Soft-Start
- Open/Shorted LED Protection
- PWM Brightness Control
- LED Current Matching Typically <2.5%
- Constant Frequency 1MHz Operation
- Low Shutdown Current: 6.5µA
- Overtemperature Protection
- Small Thermally Enhanced 20-Lead (4mm × 4mm) QFN Package
Typical Application
Description
The LTC3452 is a synchronous buck-boost DC/DC converter optimized for driving two banks of white LEDs from a single Li-Ion battery input. Five parallel LEDs can be driven at up to 25mA each in the low power LED bank, while two LEDs can be driven at up to 150mA each (or a single LED at 300mA) in the high power LED bank. 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 by sensing which LED requires the largest forward voltage drop at its programmed current, and regulating the common output rail for lowest dropout. Efficiency of 85% can be achieved over the entire usable range of a Li-Ion battery (2.7V to 4.2V).Maximum LED current for each LED display is programmable with a single external resistor. Dual enable pins allow for PWM brightness control in the low power bank and independent on/off control for the high current bank (optimal for LED camera flash). In shutdown, the supply current is only 6.5µA.
A high constant operating frequency of 1MHz allows the use of a small external inductor. The LTC3452 is offered in a low profile (0.75mm) thermally enhanced 20-lead (4mm × 4mm) QFN package.
Packaging
For complete and up to date package information and drawings, please refer to our packaging page
QFN-20
Order Info
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) | Price (1k)* | RoHS Data |
|---|---|---|---|---|---|---|
| LTC3452EUF | QFN | 20 | E | $2.57 | $1.80 | View |
| LTC3452EUF#PBF | QFN | 20 | E | $2.57 | $1.80 | View |
| LTC3452EUF#TR | QFN | 20 | E | $1.86 | View | |
| LTC3452EUF#TRPBF | QFN | 20 | E | $1.86 | View | |
| Buy Now • Request Samples | ||||||
Demo Boards
Linear Technology demo boards are offered free of charge to qualified customers. Contact your local sales office or distributor to request a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC928A | LTC3452EUF Demo Board | Contact Factory | |
| Buy Now | |||
Applications
- Cell Phones
- Digital Cameras
- PDAs
- Portable Devices
Simulate
LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. To download LTspice IV and other FREE simulation tools, please visit our Design Simulation page.
To launch a ready to run LTspice demonstration circuit for this part:
- Step 1: If you have not installed LTspice on this computer, download and install LTspice IV
- Step 2: Once LTspice is installed, click on the link(s) below to launch the simulation
- Step 3: If LTspice IV does not automatically open after clicking the link above, you can instead run the simulation by right clicking on the link and selecting "Save Target As". After saving the file to your computer, start LTspice and open the demonstration circuit by selecting 'Open' from the 'File' menu
To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.
Related models available in LTspice IV
LTC3452
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.