Overview
Features and Benefits
- 0V to 36V Wide Operating Range (60V Tolerant)
- Drives Large External N-Channel MOSFETs for High Output Current Applications
- Accurately Limits Inrush Current
- Connects Highest Priority Valid Supply to Output Load
- Changes Channel Priority in Real Time
- ±2% OV, UV Input Comparators
- Individually Adjustable Current Limit Time-Out for Each Channel
- Adjustable Input Validation Time
- Fast Switchover Minimizes VOUT Droop
- 36-Lead 5mm × 6mm QFN and SSOP Packages
Product Details
The LTC4421 connects one of two input supplies to a common output based on user-defined priority and validity. By definition, the supply connected to V1 is the higher priority supply, although this can be changed dynamically. External resistive dividers set the undervoltage and overvoltage thresholds that bound the valid voltage window.
Strong gate drivers switch the large external N-channel MOSFETs quickly. Fast switchover circuitry minimizes output droop when changing channels while preventing reverse and cross conduction. A fast comparator detects input short circuits and quickly turns off the N-channel MOSFETs to minimize disruption.
External sense resistors set the maximum inrush and current limit currents. During current limiting, the LTC4421 controls the N-channel MOSFET gate to regulate 25mV across the sense resistor. When the sense resistor voltage has been regulated to 25mV for a user-settable time, the channel is disconnected and a fault is set.
Applications
- High Reliability Systems
- Server Based Back-Up Systems
- Industrial Handheld Instruments
- Battery Back-Up Systems
Product Categories
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 (1)
Documentation & Resources
-
R547 Reliability Data3/26/2018
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DC2866A - Demo Manual (Rev. 0)3/17/2020
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Ideal Diodes and Prioritizers6/8/2018
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.
Models for the following parts are available in LTspice:
LTC4421
Design Tools
ZIP
LTC4421 Design Tool
1.47 M
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.View our quality and reliability program and certifications for more information.
PCN-PDN Information
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Sample & Buy
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Buy Now Pricing
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List Pricing
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Lead Times
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Sampling
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Evaluation Boards
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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.