LTC3403
PRODUCTION1.5MHz, 600mA Synchronous Step-Down Regulator with Bypass Transistor
- Part Models
- 2
- 1ku List Price
- Starting From $3.61
Overview
- Dynamically Adjustable Output from 0.3V to 3.5V
- Very Low Quiescent Current: Only 20µA During Operation
- 600mA Output Current
- Internal P-Channel MOSFET Bypass Transistor
- High Efficiency: Up to 96%
- 1.5MHz Constant Frequency Operation
- No Schottky Diode Required
- Low Dropout Operation: 100% Duty Cycle
- 2.5V to 5V Input Voltage Range
- Drives Optional External P-Channel MOSFET
- Shutdown Mode Draws < 1µA Supply Current
- Current Mode Operation for Excellent Line and Load Transient Response
- Overtemperature Protected
- Available in 8-Lead 3mm x 3mm DFN Package
The LTC3403 is a high efficiency monolithic synchronous buck regulator optimized for WCDMA power amplifier applications. The output voltage can be dynamically programmed from 0.3V to 3.5V. At VOUT > 3.6V an internal bypass P-channel MOSFET connects VOUT directly to VIN, eliminating power loss through the inductor. Selectable forced continuous mode enables fast VOUT response to the controlling input.
Supply current is only 20µA in Burst Mode® operation and drops to <1µA in shutdown. The 2.5V to 5V input voltage range makes the LTC3403 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems.
Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode.
The LTC3403 is available in a low profile 8-lead 3mm x 3mm DFN package.
Applications
- WCDMA Cell Phone Power Amplifiers
- Wireless Modems
Documentation
Data Sheet 1
User Guide 1
Technical Articles 1
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. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LTC3403EDD#PBF | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) | ||
| LTC3403EDD#TRPBF | 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP) |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Power System Management (PSM) & Sequencers 1 | ||
| LTC2974 | RECOMMENDED FOR NEW DESIGNS | 4-Channel PMBus Power System Manager Featuring Accurate Output Current Measurement |
| Supervisory Circuits & Reset ICs 1 | ||
| LTC2934 | PRODUCTION | Ultra-Low Power Adjustable Supervisor with Power-Fail Output |
| Switching Regulators & Controllers 1 | ||
| LTC3880 | RECOMMENDED FOR NEW DESIGNS | Dual Output PolyPhase Step-Down DC/DC Controller with Digital Power System Management |
Tools & Simulations
LTspice
Models for the following parts are available in LTspice:
- LTC3403
LTpowerCAD 1
Design tools for the following parts are available in LTpowerCAD:
- LTC3403
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.
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
Evaluation Kits
LTC3403EDD | WCDMA Cellular Phone Buck Regulator, 2.7V to 5V Input, Output @ 600mA
Resources
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