Features

• Allows Safe Board Insertion and Removal from a Live, CompactPCI™ Bus
• Controls –12V, 3.3V, 5V and 12V Supplies
• Adjustable Foldback Current Limit with Circuit Breaker
• Dual-Level Circuit Breakers Protect 5V and 3.3V Supplies from Overcurrent and Short-Circuit Faults
• LOCAL_PCI_RST# Logic On-Chip
• PRECHARGE Output Biases I/O Pins During Card Insertion and Extraction
• Adjustable Supply Voltage Power-Up Rate

Typical Application

Description

The LTC®1644 is a Hot Swap™ controller that allows a board to be safely inserted and removed from a CompactPCI bus slot. External N-channel transistors control the 3.3V/5V supplies, while on-chip switches control the –12V and 12V supplies. The 3.3V and 5V supplies can be ramped up at a programmable rate. Electronic circuit breakers protect all four supplies against overcurrent faults. The PWRGD output indicates when all of the supply voltages are within tolerance. The OFF/ON pin is used to cycle the board power or reset the circuit breaker. The PRECHARGE output can be used to bias the bus I/O pins during card insertion and extraction. PCI_RST# is combined on-chip with HEALTHY# in order to generate LOCAL_PCI_RST#.