LTC3875
Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation
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Overview
Features and Benefits
- Low Value DCR Current Sensing
- Programmable DCR Temperature Compensation
- ±0.5% 0.6V Output Voltage Accuracy
- Dual True Remote Sensing Differential Amplifiers
- Phase-Lockable Fixed Frequency 250kHz to 720kHz
- Dual, 180° Phased Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
- 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 Packages
- AEC-Q100 Qualified for Automotive Applications
Product Details
The LTC3875 is a dual output current mode synchronous step-down DC/DC controller that drives all N-channel power MOSFET stages. It employs a unique architecture that enhances the signal-to-noise ratio of the current sense signal, allowing the use of very low DC resistance (DCR) power inductors to maximize efficiency in high current applications. This feature also reduces the switching jitter commonly found in low DCR applications with current mode control.
The LTC3875 features two high speed differential amplifiers which can be used to compensate for the voltage drop from the LTC3875 to the load. Its DCR temperature compensated adjustable over current trip points from 10mV to 30mV limits the maximum output current precisely over temperature.
A unique thermal balancing function adjusts per phase current to minimize the thermal stress for multichip single output applications. The LTC3875 is available in the 40- lead 6mm × 6mm (0.5mm pitch) and 40-lead 5mm × 5mm (0.4mm pitch) QFN packages.
APPLICATIONS
- Servers and Instruments
- Telecom Systems
- DC Power Distribution Systems
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (4)
Documentation & Resources
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R526 Reliability Data3/26/2018PDF365 K
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DC2225A - Demo Manual4/1/2016PDF583K
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DC2055A - Demo Manual3/10/2016PDF913K
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DC2142A - Demo Manual6/5/2014PDF759K
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DC2000A - Demo Manual2/27/2014PDF545K
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LTC3874 Video Product Brief10/15/2018 -
LTC3875 Video Product Brief10/15/2018
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
LTspice Simulations
Models for the following parts are available in LTspice:
LTC3875
LTpowerCAD
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
Design tools for the following parts are available in LTpowerCAD:
LTC3875
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Support & Discussions
LTC3875 Discussions
Sample & Buy
See our Ordering FAQs for answers to questions about online orders, payment options and more.
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Sampling:
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.