特点
Allows Safe Board Insertion and Removal from a Live Backplane
Controls Three Supply Voltages from 1.7V to 16.5V with V
CC1
>or= V
CC2
>or= V
CC3
Programmable Soft-Start with Inrush Current Limiting, No External Gate Capacitor Required
Faster Turn-Off Time with No Gate Capacitor
Dual Level Overcurrent Fault Protection
Programmable Overcurrent Response Time
Programmable Overvoltage Protection
Automatic Retry or Latched Mode Operation
Independent N-Channel FET High Side Drivers
User-Programmable Supply Voltage Power-Up Rate
FB
n
Pin Monitors V
OUT
n
and Signals RESET
n
Glitch Filter Eliminates Spurious RESET
n
Signals
典型应用
描述
The LTC?4230 is a 3-channel Hot Swap? controller that allows a board to be safely inserted and removed from a live backplane. Internal high side switch drivers control the gates of external N-channel MOSFETs for supply voltages ranging from 1.7V to 16.5V. The LTC4230 provides soft-start and inrush current limiting during the programmable start-up period.
On-chip current limit comparators provide dual level circuit breaker protection. The slow comparators trip at V CC n –50mV and activate in 10μs or are programmed by an external filter capacitor. The fast comparators trip at V CC n –150mV and typically respond in 500ns.
Each FB n pin monitors its own output supply voltage and signals its RESET pin. The ON pin turns the chip on and off and can be used for a reset function. The LTC4230 also provides additional functions including fault indication, autoretry or latchoff modes, programmable current limit response time based on the FAULT and FILTER pins’ functionality.