LTC4236 - Dual Ideal Diode-OR and Single Hot Swap Controller with Current Monitor


  • Ideal Diode-OR and Inrush Current Control for Redundant Supplies
  • Low Loss Replacement for Power Schottky Diodes
  • Enables Safe Board Insertion into a Live Backplane
  • 2.9V to 18V Operating Range
  • Current Monitor Output
  • Controls N-Channel MOSFETs
  • Limits Peak Fault Current in ≤ 1μs
  • Adjustable Current Limit with Foldback
  • Adjustable Start-Up and Current Limit Fault Delay
  • 0.5μs Ideal Diode Turn-On and Turn-Off Time
  • Smooth Switchover without Oscillation
  • Fault, Power Good and Diode Status Outputs
  • LTC4236-1: Latch Off After Fault
  • LTC4236-2: Automatic Retry After Fault
  • 28-Pin 4mm x 5mm QFN Package

Typical Application

LTC4236 Typical Application
LTC4236 Typical Application


The LTC®4236 offers ideal diode-OR and Hot Swap functions for two power rails by controlling external N-channel MOSFETs. MOSFETs acting as ideal diodes replace two high power Schottky diodes and the associated heat sinks, saving power and board area. A Hot Swap control MOSFET allows a board to be safely inserted and removed from a live backplane by limiting inrush current. The supply output is also protected against short-circuit faults with a fast acting foldback current limit and electronic circuit breaker.

The LTC4236 regulates the forward voltage drop across the ideal diode MOSFETs to ensure smooth current transfer from one supply to the other without oscillation. The ideal diode MOSFETs turn on quickly to reduce the load voltage droop during supply switchover. If the input supply fails or is shorted, a fast turn-off minimizes reverse current transients.

A current sense amplifier translates the voltage across the sense resistor to a ground referenced signal. The LTC4236 provides adjustable start-up delay, turn-on/-off control, and reports fault and power good status for the supply.


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
LTC4236CUFD-1#PBF 4x5 QFN-28 UFD C 05-08-1712 Yes
LTC4236CUFD-1#TRPBF 4x5 QFN-28 UFD C 05-08-1712 Yes
LTC4236CUFD-2#PBF 4x5 QFN-28 UFD C 05-08-1712 Yes
LTC4236CUFD-2#TRPBF 4x5 QFN-28 UFD C 05-08-1712 Yes
LTC4236IUFD-1#PBF 4x5 QFN-28 UFD I 05-08-1712 Yes
LTC4236IUFD-1#TRPBF 4x5 QFN-28 UFD I 05-08-1712 Yes
LTC4236IUFD-2#PBF 4x5 QFN-28 UFD I 05-08-1712 Yes
LTC4236IUFD-2#TRPBF 4x5 QFN-28 UFD I 05-08-1712 Yes

LTC4236 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
LTC4236CUFD-1#PBF 4x5 QFN-28 C $6.07 $4.25 Yes
LTC4236CUFD-1#TRPBF 4x5 QFN-28 C $4.31 Yes
LTC4236CUFD-2#PBF 4x5 QFN-28 C $6.07 $4.25 Yes
LTC4236CUFD-2#TRPBF 4x5 QFN-28 C $4.31 Yes
LTC4236IUFD-1#PBF 4x5 QFN-28 I $6.68 $4.68 Yes
LTC4236IUFD-1#TRPBF 4x5 QFN-28 I $4.74 Yes
LTC4236IUFD-2#PBF 4x5 QFN-28 I $6.68 $4.68 Yes
LTC4236IUFD-2#TRPBF 4x5 QFN-28 I $4.74 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
DC2314A-A LTC4236-1 Demo Board | Dual Ideal Diode-OR & Single Hot Swap Controller with Current Monitor, Latch-Off Version $75.00
DC2314A-B LTC4236-2 Demo Board | Dual Ideal Diode-OR & Single Hot Swap Controller with Current Monitor, Auto-Retry Version $75.00
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