LTC4226 - Wide Operating Range Dual Hot Swap Controller


  • Allows Safe Board Insertion into Live Backplane
  • Selectable Current Limit and Dual-Rate Timer Accommodate Load Surges
  • Fast Response Limits Peak Fault Current
  • Wide Operating Voltage Range: 4.5V to 44V
  • Optional Auto-Retry or Latchoff after Overcurrent Fault
  • High Side Drive for External N-Channel MOSFET
  • Allows Parallel Power Paths for High Current Applications
  • Available in 16-Pin QFN (3mm × 3mm) and MSOP Packages

Typical Application

LTC4226 Typical Application
LTC4226 Typical Application


The LTC4226 dual Hot Swap™ controller allows two power paths to be safely inserted and removed from a live backplane or powered connector. Using N-channel pass transistors, supply voltages ranging from 4.5V to 44V are ramped up at an adjustable rate.

Three selectable ratios of current limit to circuit breaker threshold accommodate noisy loads and momentary high peak currents without interruption, while a dual-rate fault timer protects the MOSFET from extended output overcurrent events. FAULT outputs indicate the circuit breaker status.The LTC4226-1 remains off after a fault while the LTC4226-2 automatically retries after a 0.5s delay.

The LTC4226 can also be configured as a bidirectional current limiter/circuit breaker. For high current applications, two channels may be configured as parallel power paths.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LTC4226CMS-1#PBF MS-16 MS C 05-08-1669 Yes
LTC4226CMS-1#TRPBF MS-16 MS C 05-08-1669 Yes
LTC4226CMS-2#PBF MS-16 MS C 05-08-1669 Yes
LTC4226CMS-2#TRPBF MS-16 MS C 05-08-1669 Yes
LTC4226CUD-1#PBF 3x3 QFN-16 UD C 05-08-1700 Yes
LTC4226CUD-1#TRPBF 3x3 QFN-16 UD C 05-08-1700 Yes
LTC4226CUD-2#PBF 3x3 QFN-16 UD C 05-08-1700 Yes
LTC4226CUD-2#TRPBF 3x3 QFN-16 UD C 05-08-1700 Yes
LTC4226IMS-1#PBF MS-16 MS I 05-08-1669 Yes
LTC4226IMS-1#TRPBF MS-16 MS I 05-08-1669 Yes
LTC4226IMS-2#PBF MS-16 MS I 05-08-1669 Yes
LTC4226IMS-2#TRPBF MS-16 MS I 05-08-1669 Yes
LTC4226IUD-1#PBF 3x3 QFN-16 UD I 05-08-1700 Yes
LTC4226IUD-1#TRPBF 3x3 QFN-16 UD I 05-08-1700 Yes
LTC4226IUD-2#PBF 3x3 QFN-16 UD I 05-08-1700 Yes
LTC4226IUD-2#TRPBF 3x3 QFN-16 UD I 05-08-1700 Yes

LTC4226 Package Drawing
LTC4226 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LTC4226CMS-1#PBF MS-16 C $4.43 $3.10 Yes
LTC4226CMS-1#TRPBF MS-16 C $3.16 Yes
LTC4226CMS-2#PBF MS-16 C $4.43 $3.10 Yes
LTC4226CMS-2#TRPBF MS-16 C $3.16 Yes
LTC4226CUD-1#PBF 3x3 QFN-16 C $4.43 $3.10 Yes
LTC4226CUD-1#TRPBF 3x3 QFN-16 C $3.16 Yes
LTC4226CUD-2#PBF 3x3 QFN-16 C $4.43 $3.10 Yes
LTC4226CUD-2#TRPBF 3x3 QFN-16 C $3.16 Yes
LTC4226IMS-1#PBF MS-16 I $5.09 $3.57 Yes
LTC4226IMS-1#TRPBF MS-16 I $3.63 Yes
LTC4226IMS-2#PBF MS-16 I $5.09 $3.57 Yes
LTC4226IMS-2#TRPBF MS-16 I $3.63 Yes
LTC4226IUD-1#PBF 3x3 QFN-16 I $5.09 $3.57 Yes
LTC4226IUD-1#TRPBF 3x3 QFN-16 I $3.63 Yes
LTC4226IUD-2#PBF 3x3 QFN-16 I $5.09 $3.57 Yes
LTC4226IUD-2#TRPBF 3x3 QFN-16 I $3.63 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1627A-A LTC4226CUD-1 Demoboard : Dual Hot Swap Controller with Latch Off $75.00
DC1627A-B LTC4226CUD-2 Demoboard : Dual Hot Swap Controller with Auto-Retry $75.00
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Click here to view our complete list of demo boards


  • Apple FireWire/IEEE 1394
  • Disk Drives
  • Rugged 12V, 24V Applications
  • Hot Board/Connector Insertion
  • Uni/Bidirectional Current Limiter/Circuit Breaker

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