Linear 公司的LTC4280是帶I2C兼容監視的熱插拔控制器,從而允許板能安全插入和拔出帶電的背板. LTC4280的I2C接口和板上8位ADC能監視負載電流,電壓和故障狀態.工作電壓從2.9V到15V,可調過流濾波器時間,具有用于外接N-MOSFET的高邊驅動,輸入過壓/欠壓保護,主要用于帶電板的插入,電路斷路器,計算機和服務器以及平臺管理.本文介紹LTC4280主要特性, 方框圖, 帶5A斷路器的12V應用電路以及在背板中的典型應用電路.

LTC4280: Hot Swap Controller with I2C Compatible Monitoring

The LTC4280 Hot Swap? controller allows a board to be safely inserted and removed from a live backplane. Using an external N-channel pass transistor, board supply voltage
and inrush current are ramped up at an adjustable rate. An I2C interface and onboard ADC allow for monitoring of load current, voltage and fault status.

The device features adjustable analog foldback current limit and a FILTER pin which confi gures the time spent in overcurrent before declaring a fault. An I2C interface may confi gure the part to latch off or automatically restart after the LTC4280 detects a current limit fault.

The controller has additional features to interrupt the host when a fault has occurred, notify when output power is good, detect insertion of a load card, and power-up either
automatically upon insertion or wait for an I2C command to turn on.

LTC4280主要特性:

Allows Safe Insertion into Live Backplane

8-Bit ADC Monitors Current and Voltage

I2C/SMBus Interface

Wide Operating Voltage Range: 2.9V to 15V

Adjustable Overcurrent Filter Time

High Side Drive for External N-Channel MOSFET

No External Gate Capacitor Required

Input Overvoltage/Undervoltage Protection

Optional Latchoff or Auto-Retry After Faults

Alerts Host After Faults

Inrush Current Limit with Foldback

Available in 24-Pin 4mmx ?5mm QFN Package

LTC4280應用:

Live Board Insertion

Electronic Circuit Breakers

Computers, Servers

Platform Management

圖1.LTC4280方框圖

圖2.帶5A斷路器的12V應用電路

圖3.LTC4280典型應用電路圖

圖4.LTC4280 5V背板典型應用:插入激活接通和5A斷路器