原标题：TI TPS24700 2.5V到18V高效热插拔电源参考设计方案

　　TI公司的TPS24700是一款易用的驱动外部N沟道MOSFET场效应管，2.5V至18V输入支持热插拔的电源转换控制器。该控制器芯片具有可编程的电流限制和故障时间保护功能，以解决上电启动时负载或供电端极度过流。正常启动后，除在极度过载情况下立刻将负载断开外，当电流超过用户设置值时，负载并没有马上断开，只有当过流时间超过设置时间值时才会断开。本文首先介绍芯片的简介、特性、内部框图及应用领域，并给出相应设计方案的设计原理图、元器件列表及PCB元件布局图。

　　The TPS24700/1 is an easy-to-use, 2.5 V to 18 V, hot-swap controller that drives an external N-channel MOSFET. The programmable current limit and fault time protect the supply and load from excessive current at startup. After startup, currents above the user-selected limit are allowed to flow until programmed timeout – except in extreme overload events when load is immediately disconnected from source. The low, 25-mV current sense threshold is highly accurate and allows use of smaller, more-efficient sense resistors, yielding lower power loss and smaller footprint. A power-good output is provided for status monitoring and downstream load control.

　　TPS24700/1 replaces the LTC4211 in existing designs with no PCB board changes and only minor external component changes – yielding a more accurate, efficient solution.

　　TPS24700主要特性：

　　2.5-V to 18-V Operation

　　Accurate Current Limiting for Starup

　　Accurate 25-mV Current Sense Threshold

　　Timed Overcurrent Breaker

　　Power-Good Output

　　Fast Breaker for Short-Circuit Protection

　　Latch Off (TPS24700) and Retry Versions (TPS24701)

　　Programmable UV Threshold

　　Drop-In Upgrade for LTC4211 – No Layout Changes

　　Small MSOP-8 Package

　　APPLICATIONS

　　Server Backplanes

　　Storage Area Networks (SAN)

　　Medical Systems

　　Plug-In Modules

　　Base Stations

　　Consumer Electronics

　　TPS24700应用：

　　Server Backplanes

　　Storage Area Networks (SAN)

　　Medical Systems

　　Plug-In Modules

　　Base Stations

　　Consumer Electronics

　　图1. TPS24700内部方框图

　　TPS24700方案介绍：

　　The EVM is a 3-V to 20-V module using the TPS24700/01/10/11 hot-swap controller with external MOSFET. At power on, the output is power limited to control inrush current and protect the MOSFET. On an over-current condition, the controller interrupts power to the load at high speed and signals load status. Operating current, fault current and fault timer settings are hardware programmable.

　　EVM Basic Functions

　　• Board design covers input/output from 3-V to 20-V but is factory set for 12-V operation. The customer can change components to operate at other voltages and currents.

　　• Board design for 50-A steady state max output. The EVM will be set up for a 12-V, 25-A nominal application. The datasheet design examples show how to select components for other operating set points.

　　• Latch-off or re-try controller by part number.

　　• Input/output out of operating range transient voltage protections.

　　• Support components to be 0603 size where permitted by power dissipation or component ratings.

　　• 2-oz copper, 4 layer.

　　• On-board ENABLE input (slide switch).

　　TPS24700方案原理图：

　　图2. TPS24700方案原理图

　　TPS24700方案材料清单：