Quad Synchronous Step-Down Regulator: 2.25MHz, 300mA, 200mA, 200mA, 100mA

Show More showmore-icon

Info: : PRODUCTION tooltip
Info: : PRODUCTION tooltip
Part Details
Part Models 2
1ku List Price Starting From $3.54
  • 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
  • Extremely Low Channel-to-Channel Transient Crosstalk
  • Low Ripple (20mVP-P) Burst Mode Operation:
    • IQ = 70µA (All Channels On)
  • 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
Additional Details
show more Icon

The LTC3544 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 LTC3544 well suited for single Li-Ion/polymer battery-powered applications. 100% duty cycle provides low dropout operation, extending battery runtime in portable systems. Low ripple Burst Mode® operation increases efficiency at light loads, further extending battery runtime with typically only 20mV of ripple.

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 LTC3544 is available in a low profile (0.75mm) (3mm × 3mm) QFN package.

Light Load Operation
LTC3544 Burst Mode (20mVP-P), <70µa IQ
LTC3544B Pulse Skip Mode


  • Cellular Telephones
  • Personal Information Appliances
  • Wireless and DSL Modems
  • Digital Still Cameras
  • Media Players
  • Portable Instruments
Part Models 2
1ku List Price Starting From $3.54

close icon


Part Model Pin/Package Drawing Documentation CAD Symbols, Footprints, and 3D Models
  • HTML
  • HTML
  • HTML
  • HTML
Software & Part Ecosystem

Software & Part Ecosystem

Evaluation Kit

Evaluation Kits 1

reference details image


LTC3544EUD Demo Board | Quad Synchronous Buck, 2.25V ≤ VIN ≤ 5.5V, IOUT = 100mA, 200mA(×2) and 300mA



LTC3544EUD Demo Board | Quad Synchronous Buck, 2.25V ≤ VIN ≤ 5.5V, IOUT = 100mA, 200mA(×2) and 300mA

LTC3544EUD Demo Board | Quad Synchronous Buck, 2.25V ≤ VIN ≤ 5.5V, IOUT = 100mA, 200mA(×2) and 300mA

Product Detail

Demonstration circuit 1040 is a quad output regulator consisting of four constant-frequency step-down converters integrated into the LTC3544. DC1040 has an input voltage range of 2.25V to 5.5V, with regulators capable of delivering 100mA, 200mA, 200mA and 300mA of output current. The four regulators operate independently with individual RUN pins and enter pulse skipping mode at low loads to reduce output ripple. The "-A" version is for the LTC3544EUD (Burst Mode) and the "-B" version is for the LTC3544BEUD (Pulse Skipping Mode).

Tools & Simulations

Tools & Simulations 1

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.

To launch ready-to-run LTspice demonstration circuits for this part:

Step 1: Download and install LTspice on your computer.

Step 2: Click on the link in the section below to download a demonstration circuit.

Step 3: If LTspice does not automatically open after clicking the link below, 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.

Recently Viewed