ANALOG DEVICES LTC4421IUHE#PBF PowerPath Prioritiser, High Power, 3 to 36 V, -40 to 85 Deg C, QFN-EP-36

LTC4421 is a high power prioritized PowerPath controller. It connects one of two input supplies to a common output based on user-defined priority and validity. By definition, the supply connected to V1 is the higher priority supply, although this can be changed dynamically. External resistive dividers set the undervoltage and overvoltage thresholds that bound the valid voltage window. Strong gate drivers switch the large external N-channel MOSFETs quickly. Fast switchover circuitry minimizes output droop when changing channels while preventing reverse and cross conduction. A fast comparator detects input short circuits and quickly turns off the N-channel MOSFETs to minimize disruption. External sense resistors set the maximum inrush and current limit currents. It is used in applications such as high reliability systems, server based back-up system, industrial handheld instruments, battery back-up systems etc.

• 0V to 36V wide operating range (60V tolerant)
• Drives large external N-channel MOSFETs for high output current applications
• Accurately limits inrush current, changes channel priority in real time
• Connects highest priority valid supply to output load
• Individually adjustable current limit time-out for each channel
• Adjustable input validation time, fast switchover minimizes VOUT droop
• Total input supply current is 0.53mA typ at (V1, V2, OUT1, OUT2, EXTVCC, CPOREF)
• Total input supply current in shutdown is 5.4µA typ at (V1, V2, EXTVCC)
• Operating temperature range from -40°C to 85°C
• Package style is 36-lead plastic QFN