LTC4228IUFD-1 Integrated Circuit Chip Dual Ideal Diode and Hot Swap Controller 28-Lead QFN

The LTC4228IUFD-1 combines ideal diode and Hot Swap functions for two power rails by controlling two external N-channel MOSFETs in each rail. MOSFETs used as ideal diodes replace two high power Schottky diodes and their heat sinks, which saves both power and board area.

The Hot Swap MOSFETs limit inrush current so a board can be inserted into and removed from a live backplane safely. The device regulates the forward voltage drop across the external MOSFET and sense resistor to keep current transfer between the two supplies smooth and free from oscillation.

The input range is 2.9 V to 18 V. A fast current limit responds in 1 microsecond or less, the circuit breaker trip point is 50 mV typical across the sense resistor, and the fault delay is set with a capacitor on the TMR pin. Ideal diode turn-on and turn-off take 0.5 microseconds, which keeps load droop small during switchover.

Status, fault and power good outputs report the state of each rail, and the two rails can be switched independently. The LTC4228-1 version latches off after a fault, while the LTC4228-2 version retries automatically once the fault clears.

The LTC4228IUFD-1 is the industrial grade part in the 28-Lead Plastic QFN (4mm x 5mm) package, specified from -40 to 85 degrees C. It is RoHS compliant and lead free, and every order ships with full traceability. Samples and volume pricing are available on request.

• Power path and inrush current control for redundant supplies
• Low loss replacement for power Schottky diodes
• Protects output voltage from input brownouts
• Allows safe hot swapping from a live backplane
• 2.9 V to 18 V operating range
• Controls N-channel MOSFETs
• Limits peak fault current in 1 microsecond or less
• Adjustable current limit with circuit breaker
• Adjustable current limit fault delay
• Smooth switchover without oscillation
• 0.5 microsecond ideal diode turn-on and turn-off
• Status, fault and power good outputs
• Latch off after fault
• 28-Lead Plastic QFN (4mm x 5mm) package
• RoHS compliant, lead free

• Redundant power supplies
• MicroTCA systems and servers
• Telecom networks
• Power prioritizers
• Hot board and connector insertion
• Ideal diode ORing of two supplies

Typical use is a 12 V plug-in card that takes power from either of two backplane feeds without interruption.

• 15+ years of electronic components experience
• Secure ordering process
• Excellent customer feedback
• Confirmed delivery dates
• Competitive pricing on volume orders
• Global export experience with responsive after-sales support

Other product types we regularly stock and supply appear below.