Hot swap controller integrates a MOSFET & current sensing

By integrating the two most critical and largest hot swap components, the controller reduces design time and saves valuable board area in high density circuit boards. The internal MOSFET’s safe operating area is production tested and specified to ensure a rugged hot-plug solution, especially for space-constrained boards and cards in servers, network routers and switches, solid state drives and industrial systems.

Upon insertion, the LTC4234 waits for connector contact bounce to finish before soft-starting the output. A ground-referenced signal proportional to the load current is provided for monitoring with an external ADC. The current limit can be reduced from its 22.5A default with a single resistor, affording quick adjustment for dynamic load changes and various applications. For higher current applications, two controllers can be easily paralleled for a 40A solution. During overcurrent conditions, the device limits MOSFET power dissipation by folding back its current limit for an adjustable timeout period. Undervoltage and overvoltage thresholds protect downstream loads against voltages outside a valid window, preventing circuit malfunction and damage.

Specified over the 0 to 70°C commercial, -40 to 85°C industrial and -40 to 125°C automotive temperature ranges, the LTC4234 is offered in a 38-pin 5x9mm QFN package. 1,000-piece pricing starts at $4.95 each.