LTC7103 - 105V, 2.3A Low EMI Synchronous Step-Down Regulator


  • Wide VIN Range: 4.4V to 105V (110V Abs Max)
  • Ultralow EMI/EMC Emissions: CISPR 25 Compliant
  • 2µA IQ When Regulating 48VIN to 3.3VOUT
  • Fast and Accurate Output Current Programming and Monitoring with No External RSENSE
  • Brick Wall Current Limit
  • Low Minimum On-Time: 40ns
  • Wide VOUT Range: 1V to VIN
  • 100% Maximum Duty Cycle Operation
  • Programmable Fixed Frequency: 200kHz to 2MHz
  • Eight, Pin-Selectable Fixed (1.2V to 15V) or Adjustable Output Voltages
  • Selectable Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads
  • PLL Synchronization to External Clock
  • EXTVCC LDO Powers Chip from VOUT = 3.3V to 40V
  • OPTI-LOOP® or Fixed Internal Compensation
  • Input and Output Overvoltage Protection
  • Thermally Enhanced (5mm × 6mm) QFN Package

Typical Application

LTC7103 Typical Application
LTC7103 Typical Application


The LTC7103 is a high efficiency, monolithic synchronous step-down DC/DC converter utilizing a constant frequency, average current mode control architecture. It operates from an input voltage range of 4.4V to 105V and provides an adjustable regulated output voltage from 1V to V IN while delivering up to 2.3A of output current.

The LTC7103 features high frequency operation and a low minimum on-time that reduce inductor size and enable constant-frequency operation even at very high step-down ratios. In addition, the LTC7103 achieves the lowest possible dropout voltage with 100% maximum duty cycle operation. During light load operation, converter efficiency and output ripple can be optimized by selecting Burst Mode or pulse-skipping operation.

The LTC7103 includes accurate, high speed average cur- rent programming and monitoring without the need for an external sense resistor. Additional features include a bypass LDO to maximize efficiency, fixed or adjustable output voltage and loop compensation, and a wide array of protection features to enhance reliability.


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

Part Number Package Code Temp Package
LTC7103EUHE#PBF 5x6 QFN-36 UHE E 05-08-1983 Yes
LTC7103EUHE#TRPBF 5x6 QFN-36 UHE E 05-08-1983 Yes
LTC7103HUHE#PBF 5x6 QFN-36 UHE H 05-08-1983 Yes
LTC7103HUHE#TRPBF 5x6 QFN-36 UHE H 05-08-1983 Yes
LTC7103IUHE#PBF 5x6 QFN-36 UHE I 05-08-1983 Yes
LTC7103IUHE#TRPBF 5x6 QFN-36 UHE I 05-08-1983 Yes
LTC7103MPUHE#PBF 5x6 QFN-36 UHE MP 05-08-1983 Yes
LTC7103MPUHE#TRPBF 5x6 QFN-36 UHE MP 05-08-1983 Yes

LTC7103 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
LTC7103EUHE#PBF 5x6 QFN-36 E $6.43 $4.50 Yes
LTC7103EUHE#TRPBF 5x6 QFN-36 E $6.49 $4.56 Yes
LTC7103HUHE#PBF 5x6 QFN-36 H $7.43 $5.20 Yes
LTC7103HUHE#TRPBF 5x6 QFN-36 H $7.49 $5.26 Yes
LTC7103IUHE#PBF 5x6 QFN-36 I $7.07 $4.95 Yes
LTC7103IUHE#TRPBF 5x6 QFN-36 I $7.13 $5.01 Yes
LTC7103MPUHE#PBF 5x6 QFN-36 MP $20.06 $14.04 Yes
LTC7103MPUHE#TRPBF 5x6 QFN-36 MP $20.12 $14.10 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
DC2317A LTC7103 Demo Board | VIN = 5V to 100V with VOUT = 5V at 2.3A @400kHz $245.00
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