LT8601 - 42V Triple Monolithic Synchronous Step-Down Regulator


  • Flexible Power Supply System Providing Three Outputs Over a Wide Input Voltage Range
  • Two High Voltage Synchronous Buck Regulators
  • 3V to 42V Input Voltage Range
  • Output Currents Up to 2.5A and 1.5A
  • High Efficiency Up to 93%
  • One Low Voltage Synchronous Buck Regulator
  • 2.6V to 5.5V Input Voltage Range
  • Output Current Up to 1.8A and 95% Efficiency
  • Resistor Programmable and Synchronizable from 250kHz to 2.2MHz Switching Frequency
  • Low Ripple Burst Mode® Operation
  • 30μA IQ at 12VIN to 3.3VOUT2
  • Output Ripple <15mV
  • Programmable Power-On Reset
  • Power Good Indicators
  • 2-Phase Clock Reduces Input Current Ripple
  • Available in Thermally Enhanced 40-Lead QFN (6mm × 6mm) Package

Typical Application

LT8601 Typical Application
LT8601 Typical Application
LT8601 Typical Application


The LT®8601 is a triple channel, current mode, monolithic buck switching regulator with a programmable power-on reset. All regulators are synchronized to a single oscillator with an adjustable frequency from 250kHz to 2.2MHz. The LT8601 can be configured for micropower Burst Mode or Pulse-Skipping operation at light load. Micropower operation results in quiescent current of 30μA with all three regulators operating as shown in the application below with no load applied.

The high voltage channels are synchronous buck regulators that operate from an input of 3.0V to 42V. The output currents are up to 1.5A (OUT1) and 2.5A (OUT2). The low voltage channel operates from an input of 2.6V to 5.5V. Internal synchronous power switches provide high efficiency with output currents up to 1.8A. The LT8601 uses a 2-phase clock with channel 1 operating 180° from channels 2 and 3 to reduce input ripple current on both HV and LV inputs. All channels have cycle-by-cycle current limit, providing protection against shorted outputs. Thermal shutdown provides additional protection.

The LT8601 is available in a 40-lead 6mm × 6mm QFN package.


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

Part Number Package Code Temp Package
LT8601EUJ#PBF 6x6 QFN-40 UJ E 05-08-1728 Yes
LT8601EUJ#TRPBF 6x6 QFN-40 UJ E 05-08-1728 Yes
LT8601IUJ#PBF 6x6 QFN-40 UJ I 05-08-1728 Yes
LT8601IUJ#TRPBF 6x6 QFN-40 UJ I 05-08-1728 Yes

LT8601 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
LT8601EUJ#PBF 6x6 QFN-40 E $7.36 $5.15 Yes
LT8601EUJ#TRPBF 6x6 QFN-40 E $7.42 $5.21 Yes
LT8601IUJ#PBF 6x6 QFN-40 I $8.10 $5.67 Yes
LT8601IUJ#TRPBF 6x6 QFN-40 I $8.16 $5.73 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
DC2346A LT8601EUJ Demo Board | Triple Sync Buck, 6V ≤ VIN ≤ 24V, 5Vout1 @ 1.5A, 3.3Vout2 @ 2.5A and 1.8Vout3 @ 1.8A, 2MHz FSW $309.00
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Click here to view our complete list of demo boards


  • Automotive Systems
  • Distributed Supply Regulation
  • Industrial Controls and Power Supplies

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Design Tools


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

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The LTpowerCAD design tool is a complete power supply design tool program that can significantly ease the tasks of power supply design. It guides users to a solution, selects power stage components, provides detailed power efficiency, shows quick loop bode plot stability and load transient analysis, and can export a final design to LTspice for simulation. Click here to download LTpowerCAD

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