LTC2974 - 4-Channel PMBus Power System Manager Featuring Accurate Output Current Measurement


  • Order Custom Programmed Parts
  • Sequence, Trim, Margin and Supervise Four Power Supplies
  • Manage Faults, Monitor Telemetry and Create Fault Logs
  • PMBus Compliant Command Set
  • Supported by LTpowerPlayTM GUI
  • Margin or Trim Supplies to 0.25% Accuracy
  • Fast OV/UV Supervisors Per Channel
  • Fast Output Current Supervisors Per Channel
  • Coordinate Sequencing and Fault Management Across Multiple Chips
  • Automatic Fault Logging to Internal EEPROM
  • Operate Autonomously without Additional Software
  • External Temperature and Input Voltage Supervisors
  • Accurate Monitoring of Four Output Voltages, Four Output Currents, Four External Temperatures, Input Voltage and Internal Die Temperature
  • I2C/SMBus Serial Interface
  • Can Be Powered from 3.3V, or 4.5V to 15V
  • Available in 64-Lead 9mm × 9mm QFN Package
  • LTpowerPlay Configuration and Development Tool

Typical Application

LTC2974 Typical Application
LTC2974 Typical Application


The LTC®2974 is a 4-channel Power System Manager used to sequence, trim (servo), margin, supervise, manage faults, provide telemetry and create fault logs. PMBus commands support power supply sequencing, precision point-of-load voltage adjustment and margining. DACs use a proprietary soft-connect algorithm to minimize supply disturbances. Supervisory functions include over and under current, voltage and temperature threshold limits for four power supply output channels as well as over and under voltage threshold limits for a single power supply input channel. Programmable fault responses can disable the power supplies with optional retry after a fault is detected. Faults that disable a power supply can automatically trigger black box EEPROM storage of fault status and associated telemetry. An internal 16-bit ADC monitors four output voltages, four output currents, four external temperatures, one input voltage and die temperature. Output power is also calculated. A programmable watchdog timer monitors microprocessor activity for a stalled condition and resets the microprocessor if necessary. A single wire bus synchronizes power supplies across multiple LTC power system management devices. Configuration EEPROM supports autonomous operation without additional software.


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

Part Number Package Code Temp Package
LTC2974CUP#PBF 9x9 QFN-64 UP C 05-08-1705 RoHS
LTC2974CUP#TRPBF 9x9 QFN-64 UP C 05-08-1705 RoHS
LTC2974IUP#PBF 9x9 QFN-64 UP I 05-08-1705 RoHS
LTC2974IUP#TRPBF 9x9 QFN-64 UP I 05-08-1705 RoHS

LTC2974 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Temp Price
LTC2974CUP#PBF 9x9 QFN-64 C $12.64 $8.85 View
LTC2974CUP#TRPBF 9x9 QFN-64 C $8.91 View
LTC2974IUP#PBF 9x9 QFN-64 I $14.54 $10.18 View
LTC2974IUP#TRPBF 9x9 QFN-64 I $10.24 View
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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
DC1508B-B LTC2974, LTC2975 Socketed Programming Board [requires DC1613] $95.00
DC1962C Power System Management Demo Board (PowerStick): 14-Supply Management with LTC2977, LTC2974 & LTC3880 [Requires DC1613] $95.00
DC1962C-KIT Starter Kit for Power System Management [Includes DC1962C, DC1613A] $125.00
DC1978A LTC2974 Demoboard Kit (includes DC1809 + DC1810), requires DC1613 $200.00
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Companion Boards

Part Number Description Price Documentation
DC1613A USB-to-PMBus Controller $50.00
DC2026C Linduino One Isolated Arduino-Compatible Demonstration Board $75.00
DC2294A DC2294A - PSM Linduino One Shield [requires DC2026, CA2978] $50.00
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Click here to view our complete list of demo boards


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Design Tools


LTpowerPlay is a powerful development environment supporting Linear Technology's Digital Power System Management (PSM) products, providing unprecedented diagnostic and debug features.

Click here to download LTpowerPlay

LTpowerPlay is the FREE Graphical User Interface (GUI) software provided by Linear Technology for use with our family of digital power products. LTpowerPlay provides unprecedented diagnostic and debug features. It becomes a valuable diagnostic tool during board bring-up to program or tweak the power management scheme in a system or to diagnose power issues when bringing up rails.

  • Download LTpowerPlay software
  • When LTpowerPlay launches the first time, it will prompt you to request a license, click 'Request a License Key...', enter the required information, then click 'Send License Request'
  • Once you have entered the registration information, you will receive an email with your license file and instructions for installing it
  • For further information, please visit
  • Access technical support documents for LTC Digital Power Products by visiting

Technical Support