1. Products
  2. Power Management
  3. Switching Regulators
  4. Step-Down (Buck) Regulators
  5. Multiple Output Buck Regulators
  6. LTC3544B


Overview

Features and Benefits

  • High Efficiency: Up to 95%
  • Four Independent Regulators Provide Up to 300mA, 200mA, 200mA and 100mA Output Current
  • 2.25V to 5.5V Input Voltage Range
  • 2.25MHz Constant Frequency Operation
  • No Schottky Diodes Required
  • Low Dropout Operation: 100% Duty Cycle
  • Pulse Skipping at Low Load for Minimum Ripple
  • 0.8V Reference Allows Low Output Voltages
  • Shutdown Mode Draws <1μA Supply Current
  • Current Mode Operation for Excellent Line and Load Transient Response
  • Overtemperature Protected
  • Low Profile (3mm × 3mm) 16-Lead QFN Package

Product Details

The LTC3544B is a quad, high efficiency, monolithic synchronous buck regulator using a constant frequency, current mode architecture. The four regulators operate independently with separate run pins. The 2.25V to 5.5V input voltage range makes the LTC3544B well suited for single Li-Ion/polymer battery-powered applications. 100% duty cycle provides low dropout operation, extending battery runtime in portable systems. At moderate and low output load levels PWM pulse skip mode operation provides very low output ripple voltage for noise sensitive applications.

Switching frequency is internally set to 2.25MHz, allowing the use of small surface mount inductors and capacitors.

The internal synchronous switches increase efficiency and eliminate the need for external Schottky diodes. Low output voltages are easily supported with the 0.8V feedback reference voltage.

The LTC3544B is available in a low profile (0.75mm) (3mm × 3mm) QFN package.

 


Light Load Operation
LTC3544 Burst Mode (20mVpp), < 70uA Iq
LTC3544B Pulse Skip Mode

Applications

  • Cellular Telephones
  • Personal Information Appliances
  • Wireless and DSL Modems
  • Digital Still Cameras
  • Media Players
  • Portable Instruments

Product Lifecycle icon-recommended 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)

Tools & Simulations

LTspice

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.

LTspice

Models for the following parts are available in LTspice:

LTC3544
LTC3544B

Product Recommendations

LTC3544B Companion Parts

Recommended Related Parts

Design Resources

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 Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LTC3544BEUD#PBF Material Declaration Reliability Data 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
LTC3544BEUD#TRPBF Material Declaration Reliability Data 16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
Wafer Fabrication Data R415 Reliability Data

Sample & Buy


Ordering FAQs


See our Ordering FAQs for answers to questions about online orders, payment options and more.

 

Buy Now Pricing


(**) Displayed Buy Now Price and Price Range is based on small quantity orders.

 

List Pricing


(*)The 1Ku 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. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

 

Lead Times


Please see the latest communication from our CCO regarding lead times.

 

Sampling


A Sample link will be shown above, next to the part, only for parts that are included in our sample program. Selecting the Sample button will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.


Price Table Help

 

Evaluation Boards

Pricing displayed is based on 1-piece.

Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.