LTC3531 - 200mA Buck-Boost Synchronous DC/DC Converters


  • Regulated Output with Input Above, Below or Equal to the Output
  • Single Inductor
  • Up to 90% Efficiency
  • VIN Range: 1.8V to 5.5V
  • 200mA at 3.3VOUT from 3.6V Input
  • 125mA at 3VOUT from 2.5V Input
  • Fixed VOUT Versions (TSOT, DFN): 3.3V, 3V
  • Adjustable VOUT Version (DFN): 2V to 5V
  • Burst Mode® Operation, No External Compensation
  • Ultra Low Quiescent Current: 16μA, Shutdown Current <1μA
  • Only 3 External Components Required
    (Fixed Voltage Versions)
  • Short-Circuit Protection
  • Output Disconnect in Shutdown
  • Available in 6-Pin ThinSOT and 3mm × 3mm DFN Packages

Typical Application

LTC3531 Typical Application
LTC3531 Typical Application


The LTC3531/LTC3531-3.3/LTC3531-3 are synchronous buck-boost DC/DC converters that operate from input voltages above, below or equal to the output voltage. The topology incorporated in the ICs provides a continuous transfer through all operating modes, making the product ideal for single cell Li-Ion and multicell alkaline or nickel applications. The converters operate in Burst Mode, minimizing solution footprint and component count as well as providing high conversion efficiency over a wide range of load currents.

The devices include two 0.5Ω N-channel MOSFET switches and two P-channel switches (0.5Ω, 0.8Ω). Quiescent current is typically 16μA, making the parts ideal for battery power applications. Other features include a <1uA shutdown current, current limiting, thermal shutdown and output disconnect. The parts are offered in a 6-pin ThinSOT package for fi xed voltage versions or a 3mm × 3mm DFN package for fixed and adjustable versions.


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
LTC3531EDD-3.3#PBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531EDD-3.3#TRPBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531EDD-3#PBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531EDD-3#TRPBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531EDD#PBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531EDD#TRPBF 3x3 DFN-8 DD E 05-08-1698 Yes
LTC3531ES6-3.3#TRMPBF SOT-23 S6 E 05-08-1636 Yes
LTC3531ES6-3.3#TRPBF SOT-23 S6 E 05-08-1636 Yes
LTC3531ES6-3#TRMPBF SOT-23 S6 E 05-08-1636 Yes
LTC3531ES6-3#TRPBF SOT-23 S6 E 05-08-1636 Yes

LTC3531 Package Drawing
LTC3531 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
LTC3531EDD-3.3#PBF 3x3 DFN-8 E $2.79 $1.95 Yes
LTC3531EDD-3.3#TRPBF 3x3 DFN-8 E $2.01 Yes
LTC3531EDD-3#PBF 3x3 DFN-8 E $2.79 $1.95 Yes
LTC3531EDD-3#TRPBF 3x3 DFN-8 E $2.01 Yes
LTC3531EDD#PBF 3x3 DFN-8 E $2.79 $1.95 Yes
LTC3531EDD#TRPBF 3x3 DFN-8 E $2.01 Yes
LTC3531ES6-3.3#TRMPBF SOT-23 E $2.86 $2.02 Yes
LTC3531ES6-3.3#TRPBF SOT-23 E $2.86 $2.00 Yes
LTC3531ES6-3#TRMPBF SOT-23 E $2.86 $2.02 Yes
LTC3531ES6-3#TRPBF SOT-23 E $2.86 $2.00 Yes
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* 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
DC877A LTC3531ES6-3.3 | 200mA Buck-Boost Synch Converter $75.00
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