LTC1503 - High Efficiency Inductorless Step-Down DC/DC Converter


  • Input Voltage Range: 2.4V to 6V
  • Fixed Output Voltages: 1.8V ±4%, 2V ±4%
  • Output Current: 100mA
  • No Inductors
  • Typical Efficiency 25% Higher than LDOs
  • Low Operating Current: 25µA
  • Low Shutdown Current: 5µA
  • 600kHz Switching Frequency
  • Shutdown Disconnects Load from VIN
  • Soft-Start Limits Inrush Current at Turn-On
  • Short-Circuit and Overtemperature Protected
  • Available in 8-Pin MSOP and SO Packages

Typical Application

LTC1503 Typical Application
LTC1503 Typical Application


The LTC1503-1.8/LTC1503-2 are switched capacitor step-down DC/DC converters that produce a regulated output from a 2.4V to 6V input. The parts use switched capacitor fractional conversion to achieve high efficiency over the entire input range. No inductors are required. Internal circuitry controls the step-down conversion ratio to optimize efficiency as the input voltage and load conditions vary. Typical efficiency is 25% higher than that of a low dropout (LDO) linear regulator.

Regulation is achieved by sensing the output voltage and enabling the internal switching network as needed to maintain a fixed output voltage. This method of regulation enables the parts to achieve high efficiency at extremely light loads. Low operating current (25µA with no load, 5µA in shutdown) and low external parts count (two 1µF flying capacitors and two 10µF bypass capacitors) make the LTC1503-1.8/LTC1503-2 ideally suited for space constrained battery-powered applications. The parts are fully short-circuit and over temperature protected.

The LTC1503-1.8/LTC1503-2 are available in 8-pin MSOP and SO packages.


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
LTC1503CMS8-1.8#PBF MS-8 MS8 C 05-08-1660 Yes
LTC1503CMS8-1.8#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC1503CMS8-2#PBF MS-8 MS8 C 05-08-1660 Yes
LTC1503CS8-1.8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1503CS8-1.8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1503CS8-2#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1503CS8-2#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1503IS8-1.8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LTC1503IS8-1.8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes
LTC1503IS8-2#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LTC1503IS8-2#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes

LTC1503 Package Drawing
LTC1503 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
LTC1503CMS8-1.8#PBF MS-8 C $2.20 $1.90 Yes
LTC1503CMS8-1.8#TRPBF MS-8 C $1.96 Yes
LTC1503CMS8-2#PBF MS-8 C $2.20 $1.90 Yes
LTC1503CS8-1.8#PBF SO-8 C $2.00 $1.70 Yes
LTC1503CS8-1.8#TRPBF SO-8 C $1.76 Yes
LTC1503CS8-2#PBF SO-8 C $2.00 $1.70 Yes
LTC1503CS8-2#TRPBF SO-8 C $1.76 Yes
LTC1503IS8-1.8#PBF SO-8 I $2.45 $2.05 Yes
LTC1503IS8-1.8#TRPBF SO-8 I $2.11 Yes
LTC1503IS8-2#PBF SO-8 I $2.45 $2.05 Yes
LTC1503IS8-2#TRPBF SO-8 I $2.11 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
DC250A-A LTC1503CMS8-2 | High Efficiency Inductorless Step-Down DC/DC Converter, 2.4 to 6Vin, 2Vout @ 100mA $100.00
DC250A-B LTC1503CMS8-1.8 | High Efficiency Inductorless Step-Down DC/DC Converter, 2.4 to 6Vin, 1.8Vout @ 100mA $100.00
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Click here to view our complete list of demo boards


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