Press Release

Contact Doug Dickinson

Hot Swap Controller Allows I2C Monitoring of Board-Level Operation

May 20 2010 - MILPITAS, CA
  • Linear Technology Corporation introduces the LTC4280, a 2.9V to 15V Hot Swap™ controller that features an on-board 8-bit ADC and I2C compatible interface. Integrated digital power monitoring enables sophisticated platform management in high-availability systems, measuring card voltages and currents, as well as recording past and present fault conditions. In such systems, careful monitoring of the health and integrity of the power distribution network is crucial. Information in the ADC registers can be queried via the I2C bus and then used to determine if a card is actually using its allocated power or operating abnormally. The LTC4280 allows an irregular card to be flagged for service before it fails, thereby improving system reliability.

    The LTC4280 is suitable for a wide range of applications, including redundant supply 12V systems subject to line transients when supplies switch over. Board supply voltages and inrush current are ramped up at an adjustable rate. The LTC4280 has an adjustable circuit breaker filter time and a 26mV current limit to accommodate a wide variety of input line and output line transients. Undervoltage and overvoltage thresholds are also independently adjustable. The controller disconnects the load if it remains in current limit beyond the time-out delay specified and can be configured to latch off or auto-retry following the event. The LTC4280 has additional features to interrupt the host when a fault has occurred, notify when output power is good, detect insertion of a board and turn off the pass transistor if an external supply monitor fails to indicate power good within a timeout period.

    The LTC4280 is offered in commercial and industrial versions, supporting operating temperature ranges from 0ºC to 70ºC and –40ºC to 85ºC, respectively. The LTC4280 is available in a RoHS-compliant 24-pin 4mm × 5mm QFN package. Pricing starts at $3.95 each in 1,000 piece quantities and is now available in production quantities. The LTC4280 complements Linear Technology's LTC4260 and LTC4261, positive and negative high voltage Hot Swap™ controllers that also feature on-board ADCs and I2C interfaces. Please visit for more product selection and information.

    Summary Features LTC4280

    • Allows Safe Insertion into Live Backplane
    • 8-Bit ADC Monitors Current & 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 (4mm × 5mm) QFN Package

    Hot Swap Controller with Current & Voltage Monitoring

  • Editor's Contact Information
Stay Informed