LTC3875 - Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation

Features

  • Dual, 180° Phased Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
  • Low Value DCR Current Sensing
  • ±0.5% 0.6V Output Voltage Accuracy
  • Optional Fast Transient Operation
  • Phase-Lockable Fixed Frequency 250kHz to 720kHz
  • Dual True Remote Sensing Differential Amplifiers
  • Programmable DCR Temperature Compensation
  • Dual N-Channel MOSFET Synchronous Drive
  • Wide VIN Range: 4.5V to 38V Operation
  • Output Voltage Range with Low DCR: 0.6V to 3.5V,without Low DCR: 0.6V to 5V
  • Adjustable Soft-Start Current Ramping or Tracking
  • Foldback Output Current Limiting
  • Clock Input and Output for Up to 12-Phase Operation
  • Short-Circuit Soft Recovery
  • Output Overvoltage Protection
  • Power Good Output Voltage Monitor
  • 40-Lead QFN Package

Typical Application

LTC3875 Typical Application
LTC3875 Typical Application

Description

The LTC®3875 is a dual output current mode synchronous step-down DC/DC controller that drives all N-channel synchronous power MOSFET stages. It employs a unique architecture which enhances the signal-to-noise ratio of the current sense signal, allowing the use of very low DC resistance power inductors to maximize the efficiency in high current applications. This feature also reduces the switching jitter commonly found in low DCR applications.

The LTC3875 features two high speed remote sense differential amplifiers, programmable current sense limits from 10mV to 30mV and DCR temperature compensation to limit the maximum output current precisely over temperature.

A unique thermal balancing function adjusts per phase current in order to minimize the thermal stress for multichip single output applications. The LTC3875 also features a precise 0.6V reference with guaranteed accuracy of ±0.5% that provides an accurate output voltage from 0.6V to 3.5V. A 4.5V to 38V input voltage range allows it to support a wide variety of bus voltages. The LTC3875 is available in a low profile 40-lead 6mm × 6mm QFN package.

Packaging

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

QFN-40

LTC3875 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price (1-99) Price (1k)* RoHS Data
LTC3875EUJ#PBF QFN 40 E $4.96 $3.47 View
LTC3875EUJ#TRPBF QFN 40 E $3.53 View
LTC3875IUJ#PBF QFN 40 I $5.22 $3.65 View
LTC3875IUJ#TRPBF QFN 40 I $3.71 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
DC2000A LTC3875EUJ Demo Board | 4.5V ≤ VIN ≤ 14V; VOUT1 = 1.0V @ 30A, VOUT2 = 1.5V @ 30A. Contact Factory
DC2055A LTC3875EUJ Demo Board | 4.5V ≤ VIN ≤ 14V; VOUT: 1V @ 120A. Contact Factory
DC2142A LTC3875EUJ/LTC3874IUFD Demo Board | 4.5V ≤ VIN ≤ 14V; VOUT: 1V @ 120A. Contact Factory
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Click here to view our complete list of demo boards

Applications

  • Servers and Instruments
  • Telecom Systems
  • DC Power Distribution Systems

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LTC3875

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