The MAX5943AEEE+ is a FireWire current limiter and low-drop ORing switch controller in 16 pin QSOP package. This device controls two external power n-channel MOSFETs to regulate current from the input power supply to the load and performs low voltage-drop, power-supply ORing. The MAX5943 FireWire/IEEE 1394 protective circuit is UL recognized. The MAX5943 allows the safe insertion and removal of FireWire peripherals into a live FireWire port by providing inrush current control and an output current-limiting function. The ORing feature provides a very efficient way to protect the FireWire port when connected to another FireWire peripheral that sources a higher voltage. By turning off both external MOSFETS, the MAX5943 provides a true bidirectional load disconnect. A low-current shutdown mode disables the MAX5943, resulting in less than 10μA supply current. A pin-selectable input allows latched or autoretry fault management after a fault.
Supply voltage range is 7.5V to 37V
Operating temperature range from -40°C to 85°C
Low drop power ORing with ultra-fast turn-off
±5% current limit sensing accuracy
Provides inrush and output current limit
ON/OFF control allows undervoltage lockout programming
Programmable active current limit
Fast current-limit response to output short circuit conditions