1. Products
  2. Power Monitor, Control, and Protection
  3. Hot Swap Controllers
  4. Low Voltage Hot Swap Controllers
  5. LTC4221


Features and Benefits

  • Allows Safe Board Insertion and Removal from a Live Backplane
  • Configurable Power Supply Sequencing
  • Soft-Start with Current Foldback Limits Inrush Current
  • No External Gate Capacitor Required
  • Adjustable Dual Level Circuit Breaker Protection
  • Controls Supply Voltages from 1V to 13.5V
  • Independent N-Channel MOSFET High Side Drivers
  • FB Pin Monitors VOUT for Overvoltage Protection
  • Latch Off or Automatic Retry on Current Fault
  • FAULT and PWRGD Outputs
  • Narrow 16-Pin SSOP Package

Product Details

The LTC4221 is a 2-channel Hot Swap controller that allows a board to be safely inserted and removed from a live backplane. Using two independent high side gate drivers to control two external N-channel pass transistors, the output voltages can be ramped up with current foldback to limit the inrush current during the start-up period. No external compensation capacitors are required at the GATE pins. The two channels can be configured to ramp up and down separately or simultaneously for supply voltages ranging from 2.7V to 13.5V and 1V to 13.5V for channels 1 and 2 respectively.

Each channel has two current limit comparators that provide dual level and dual speed overcurrent circuit breaker protection after the start-up period. If any current sense voltage exceeds 100mV for 1µs or 25mV for the timeout delay (set by the CFILTER at the FILTER pin), then the FAULT latch is set and both GATE pins are pulled low.

The FB pins monitor the respective channel output voltages and provide the inputs for the PWRGD comparators as well as overvoltage protection.


  • Electronic Circuit Breaker
  • Power Supply Sequencing
  • Live Board Insertion and Removal
  • Industrial High Side Switch/Circuit Breaker

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (1)

Tools & Simulations


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Product Recommendations

LTC4221 Companion Parts

Recommended Related Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LTC4221CGN#PBF Material Declaration Reliability Data 16-Lead SSOP (Narrow 0.15 Inch)
LTC4221CGN#TRPBF Material Declaration Reliability Data 16-Lead SSOP (Narrow 0.15 Inch)
LTC4221IGN#PBF Material Declaration Reliability Data 16-Lead SSOP (Narrow 0.15 Inch)
LTC4221IGN#TRPBF Material Declaration Reliability Data 16-Lead SSOP (Narrow 0.15 Inch)
Wafer Fabrication Data R318 Reliability Data

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Sample & Buy

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Evaluation Boards

Pricing displayed is based on 1-piece.

Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.