LT4220 - Dual Supply Hot Swap Controller

The LT4220 16-pin dual voltage Hot Swap controller allows a board to be safely inserted and removed from a live backplane. The device operates with any combination of 2.7V to 16.5V and –2.7V to –16.5V supplies. Using two external N-channel pass transistors, the board supply voltages can be ramped up at an adjustable rate. A selectable tracking mode allows dual supply tracking control for ramping the positive and negative supplies together.

The LT4220 features foldback current limit and latches off both gates if either supply remains in current limit longer than an adjustable time amount. The IC can be configured for automatic restart after a delay set by the same timer.

A power good signal indicates when the output voltages monitored by the two FB comparators are within tolerance, and the gate drive signals are at their full on voltage.

The LT4220 is available in a 16-lead narrow SSOP package.

Features
  • Hot Swap™ Controller for Positive and Negative Supplies
  • Supply Tracking Mode
  • ±2.7V to ±16.5V Operation
  • Analog Current Limit with Foldback
  • Allows Safe Board Insertion and Removal from a Live Backplane
  • Open-Collector Power Good Comparators
  • Automatic Retry or Latchoff After a Current Fault
  • Dual Undervoltage Lockout Comparator Inputs
  • Current Fault Indication
Typical Application

Applications
  • Live Board Insertion
  • RAID Systems
  • –5.2V ECL Supplies
  • Industrial Controls
  • Split Supply Systems
Packaging
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LT4220CGN#PBFSSOP-16C$5.00$3.50
LT4220CGN#TRPBFSSOP-16C$3.56
LT4220IGN#PBFSSOP-16I$4.90$4.00
LT4220IGN#TRPBFSSOP-16I$4.06
Demo Boards
Part NumberDescriptionPrice
DC665ALT4220EGN | + / - 12V, 2A Hot Swap Controller with External FETs, Vin = + / - 12V, Vout = +12V/2a, -12V/2a$75.00
Datasheet
Reliability Data
Product Selector Card
LT Journal
Related Product
LT4220 - Dual Supply Hot Swap Controller
LT4220 - 双电源热插拨控制器
R568 - Reliability Data
Hot Swap Controllers
Dec 2003 Hot Swap Controller Enforces Tracking in Split Supply Systems
LT4220 Footprints and Symbols