LTC3872 - No RSENSE Current Mode Boost DC/DC Controller

Features

  • No Current Sense Resistor Required
  • VOUT up to 60V
  • Constant Frequency 550kHz Operation
  • Internal Soft-Start and Optional External Soft-Start
  • Adjustable Current Limit
  • Pulse Skipping at Light Load
  • VIN Range: 2.75V to 9.8V
  • ±1.5% Voltage Reference Accuracy
  • Current Mode Operation for Excellent Line and Load Transient Response
  • Low Profile (1mm) SOT-23 and 2mm × 3mm DFN Packages
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LTC3872 Typical Application
LTC3872 Typical Application

Description

The LTC®3872 is a constant frequency current mode boost DC/DC controller that drives an N-channel power MOSFET and requires very few external components. The No RSENSETM architecture eliminates the need for a sense resistor, improves efficiency and saves board space.

The LTC3872 provides excellent AC and DC load and line regulation with ±1.5% output voltage accuracy. It incorporates an undervoltage lockout feature that shuts down the device when the input voltage falls below 2.3V.

High switching frequency of 550kHz allows the use of a small inductor. The LTC3872 is available in an 8-lead low profile (1mm) ThinSOTTM package and 8-pin 2mm × 3mm DFN package.

 LTC3872LTC3872-1
Frequency Foldback In Current Limit Yes 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
LTC3872EDDB#PBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3872EDDB#TRMPBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3872EDDB#TRPBF 3x2 DFN-8 DDB E 05-08-1702 Yes
LTC3872ETS8#PBF SOT-23 TS8 E 05-08-1637 Yes
LTC3872ETS8#TRMPBF SOT-23 TS8 E 05-08-1637 Yes
LTC3872ETS8#TRPBF SOT-23 TS8 E 05-08-1637 Yes
LTC3872HDDB#PBF 3x2 DFN-8 DDB H 05-08-1702 Yes
LTC3872HDDB#TRMPBF 3x2 DFN-8 DDB H 05-08-1702 Yes
LTC3872HDDB#TRPBF 3x2 DFN-8 DDB H 05-08-1702 Yes
LTC3872HTS8#PBF SOT-23 TS8 H 05-08-1637 Yes
LTC3872HTS8#TRMPBF SOT-23 TS8 H 05-08-1637 Yes
LTC3872HTS8#TRPBF SOT-23 TS8 H 05-08-1637 Yes
LTC3872IDDB#PBF 3x2 DFN-8 DDB I 05-08-1702 Yes
LTC3872IDDB#TRMPBF 3x2 DFN-8 DDB I 05-08-1702 Yes
LTC3872IDDB#TRPBF 3x2 DFN-8 DDB I 05-08-1702 Yes
LTC3872ITS8#PBF SOT-23 TS8 I 05-08-1637 Yes
LTC3872ITS8#TRMPBF SOT-23 TS8 I 05-08-1637 Yes
LTC3872ITS8#TRPBF SOT-23 TS8 I 05-08-1637 Yes


LTC3872 Package Drawing
LTC3872 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
LTC3872EDDB#PBF 3x2 DFN-8 E $2.57 Yes
LTC3872EDDB#TRMPBF 3x2 DFN-8 E $2.57 $1.85 Yes
LTC3872EDDB#TRPBF 3x2 DFN-8 E $2.57 $1.80 Yes
LTC3872ETS8#PBF SOT-23 E $2.57 Yes
LTC3872ETS8#TRMPBF SOT-23 E $2.57 $1.85 Yes
LTC3872ETS8#TRPBF SOT-23 E $2.57 $1.80 Yes
LTC3872HDDB#PBF 3x2 DFN-8 H $3.36 Yes
LTC3872HDDB#TRMPBF 3x2 DFN-8 H $3.36 $2.40 Yes
LTC3872HDDB#TRPBF 3x2 DFN-8 H $3.36 $2.35 Yes
LTC3872HTS8#PBF SOT-23 H $3.36 Yes
LTC3872HTS8#TRMPBF SOT-23 H $3.36 $2.40 Yes
LTC3872HTS8#TRPBF SOT-23 H $3.36 $2.35 Yes
LTC3872IDDB#PBF 3x2 DFN-8 I $2.96 Yes
LTC3872IDDB#TRMPBF 3x2 DFN-8 I $2.96 $2.12 Yes
LTC3872IDDB#TRPBF 3x2 DFN-8 I $2.96 $2.07 Yes
LTC3872ITS8#PBF SOT-23 I $2.96 Yes
LTC3872ITS8#TRMPBF SOT-23 I $2.96 $2.12 Yes
LTC3872ITS8#TRPBF SOT-23 I $2.96 $2.07 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
DC989B-A LTC3872ETS8 Demo Board | 2.75V ≤ VIN ≤ 4.5V; VOUT: 5V @ 2A $75.00
Buy Now
Click here to view our complete list of demo boards

Designed for Automotive and Transportation Applications

AEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LTC3872HDDB#PBF 3x2 DFN-8 H $3.36 Yes
LTC3872HDDB#TRMPBF 3x2 DFN-8 H $3.36 $2.40 Yes
LTC3872HDDB#TRPBF 3x2 DFN-8 H $3.36 $2.35 Yes
LTC3872HTS8#PBF SOT-23 H $3.36 Yes
LTC3872HTS8#TRMPBF SOT-23 H $3.36 $2.40 Yes
LTC3872HTS8#TRPBF SOT-23 H $3.36 $2.35 Yes
LTC3872IDDB#PBF 3x2 DFN-8 I $2.96 Yes
LTC3872IDDB#TRMPBF 3x2 DFN-8 I $2.96 $2.12 Yes
LTC3872IDDB#TRPBF 3x2 DFN-8 I $2.96 $2.07 Yes
LTC3872ITS8#PBF SOT-23 I $2.96 Yes
LTC3872ITS8#TRMPBF SOT-23 I $2.96 $2.12 Yes
LTC3872ITS8#TRPBF SOT-23 I $2.96 $2.07 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.

Applications

  • Telecom Power Supplies
  • 42V Automotive Systems
  • 24V Industrial Controls
  • IP Phone Power Supplies

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Design Tools

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LTC3872

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