Alternative Parts
Overview
Features and Benefits
- Selects Highest Priority Supply from Two Inputs
- Blocks Reverse and Cross Conduction Currents
- Wide Operating Voltage Range: 2.5V to 40V
- –42V Protection Against Reverse Connection
- 60V Tolerant V1, V2 Inputs
- Adjustable Input Validation Time
- Fast Switchover Minimizes Output Voltage Droop
- Low 26µA Operating Current
- ±1.5% Input Overvoltage/Undervoltage Protection
- Adjustable Overvoltage/Undervoltage Hysteresis
- Cascadable for Additional Input Supplies
- 20-Lead 4mm × 4mm QFN Package
Product Details
The LTC4418 connects one of two valid power supplies to a common output based on priority and validity. Priority is defined by pin assignment, with V1 assigned the higher priority and V2 the lower priority. A power supply is defined as valid when its voltage has been within its overvoltage (OV) and undervoltage (UV) window continuously for at least the configured validation time. If the highest priority valid input falls out of the OV/UV window, the channel is immediately disconnected and the other valid input is connected to the common output. Multiple LTC4418s, as well as triple channel LTC4417s, can be cascaded to provide switchover between more than two inputs.
The LTC4418 incorporates fast non-overlap switching circuitry to prevent both reverse and cross conduction while minimizing output droop. The gate driver includes a 6V clamp to protect external MOSFETs. A controlled soft-start feature minimizes start-up inrush current. Open drain VALID outputs indicate the input supplies have been within their OV/UV window for the duration of the validation time. The validation time can be disabled or adjusted using an external capacitor
Applications
- Industrial Handheld Instruments
- High Availability Systems
- Battery Backup Systems
- Servers and Computer Peripherals
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
Reliability Data (1)
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:
Design Tools
Reference Materials
Solutions Bulletins & Brochures (1)
Press Releases (1)
Technical Articles (1)
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
LTC4418 Discussions
Sample & Buy
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.