LTC3772 - Micropower No RSENSE Constant Frequency Step-Down DC/DC Controller

Features

  • No Current Sense Resistor Required
  • 40µA No-Load Quiescent Current
  • High Output Currents Easily Achieved
  • Internal Soft-Start Ramps VOUT
  • Wide VIN Range: 2.75V to 9.8V
  • Low Dropout: 100% Duty Cycle
  • Constant Frequency 550kHz Operation
  • Low Ripple Burst Mode® Operation at Light Load
  • Output Voltage as Low as 0.8V
  • ±1.5% Voltage Reference Accuracy
  • Current Mode Operation for Excellent Line and Load Transient Response
  • Only 8µA Supply Current in Shutdown
  • Low Profile 8-Lead SOT-23 (1mm) and (3mm × 2mm) DFN (0.75mm) Packages

Typical Application

LTC3772 Typical Application
LTC3772 Typical Application

Description

The LTC3772 is a constant frequency current mode step-down DC/DC controller in a low profile 8-lead SOT-23 (ThinSOT) and a 3mm × 2mm DFN package. The No RSENSE architecture eliminates the need for a current sense resistor, improving efficiency and saving board space.

The LTC3772 automatically switches into Burst Mode operation at light loads to increase efficiency at low output current. It consumes only 40µA of quiescent current under a no-load condition.

The LTC3772 incorporates an undervoltage lockout feature that shuts down the device when the input voltage falls below 2V. To maximize the runtime from a battery source, the external P-channel MOSFET is turned on continuously in dropout (100% duty cycle). High switching frequency of 550kHz allows the use of a small inductor and capacitors. An internal soft-start smoothly ramps the output voltage from zero to its regulation point.

  Burst Mode
LTC3772 Yes
LTC3772B No

Packaging

CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
Drawing
RoHS
LTC3772EDDB#PBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3772EDDB#TRMPBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3772EDDB#TRPBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3772ETS8#PBF SOT-23 TS8 E 05-08-1637 Yes
LTC3772ETS8#TRMPBF SOT-23 TS8 E 05-08-1637 Yes
LTC3772ETS8#TRPBF SOT-23 TS8 E 05-08-1637 Yes


LTC3772 Package Drawing
LTC3772 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • 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 Temp Price
(1-99)
Price
(1k)*
RoHS
LTC3772EDDB#PBF 3x2 DFN-8 E $2.73 Yes
LTC3772EDDB#TRMPBF 3x2 DFN-8 E $2.73 $1.93 Yes
LTC3772EDDB#TRPBF 3x2 DFN-8 E $2.73 $1.91 Yes
LTC3772ETS8#PBF SOT-23 E $2.73 Yes
LTC3772ETS8#TRMPBF SOT-23 E $2.71 $1.93 Yes
LTC3772ETS8#TRPBF SOT-23 E $2.71 $1.91 Yes
Buy NowRequest Samples
* 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 Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about 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
DC836A LTC3772EDDB Demo Board | VIN = 2.75V to 8V, VOUT = 1.8V/2.5V/3.3V @ 2A Contact Factory
Buy Now
Click here to view our complete list of demo boards

Applications

  • 1- or 2-Cell Li-Ion Battery-Powered Applications
  • Wireless Devices
  • Portable Computers
  • Distributed Power Systems

Product Notifications

Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.

Forgot your password? Click here.
Need help? Email mylinear@linear.com with questions and comments.

Design Tools

LTspice

LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

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
  • Step 2: Once LTspice is installed, click on the link(s) below to launch the simulation
  • Step 3: If LTspice 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.

Models for the following parts are available in LTspice:
LTC3772
LTC3772B

Technical Support