Maxim Integrated Products introduces the MAX5957/MAX5958 (triple) and MAX5959/MAX5960 (quad), fully integrated, 3-/4-channel hot-plug controllers for safe insertion and removal of PCI-Express (Peripheral Component Interconnect Express, PCIe) cards from live PCI-Express hot-plug slots. The target application for these controllers is high-availability systems that require 24/7 operation. Examples include servers, and storage and RAID systems.

Limitations of Traditional Dual PCI-Express Controllers

PCI-Express server systems have 1, 3, 5, 7, or more PCIe slots. Prior to the MAX5957–MAX5960, designers controlled the multiple slots with dual-channel controllers. If the application required a three-slot hot-swap controller, for example, two dual-channel controllers were used. One channel was wasted, but designers had no other choice. This design approach was neither efficient nor economical for multiple-slot systems, so customers wanted more flexibility with lower cost.

Flexibility from 3-/4-Channel Operation

The availability of 3-/4-channel control brings designers flexibility for designing multiple-slot PCIe systems. Designers can now populate a multislot PCIe system with these 3- or 4-channel controllers without wasting any channels, and thus saving both board space and cost. The MAX5957–MAX5960 provide independent power control for all three PCIe voltage rails (+12V, +3.3V, and +3.3V auxiliary supply rail) for three or four PCIe slots. The MAX5957/MAX5959 and MAX5958/MAX5960 are configured for 375mA and 550mA maximum current limit, respectively, for the +3.3V auxiliary supply rail. The devices integrate a 0.2Ω power MOSFET switch for each +3.3V auxiliary supply rail, and can be controlled with an external I/O expander through the SMBus interface.

Robust Solution for High-Availability/Storage Systems

These hot-swap controllers deliver the high level of system protection required for high-availability systems. Active inrush and overcurrent protection come with programmable overcurrent timeout. Thermal shutdown protection is also provided for each channel. Other features include: power-good status indicators with power-on reset; attention input switches with 4ms debounce; and status outputs for reporting overcurrent and thermal shutdown faults.

The devices are offered with latch-off or autorestart fault management. The MAX5957–MAX5960 operate in the -40°C to +85°C extended temperature range. The MAX5957/MAX5958 (triple) are available in a 56-pin TQFN package; the MAX5959/MAX5960 (quad) are packaged in an 80-pin TQFP. Prices start at $4.42 for the MAX5957/MAX5958 and $5.03 for the MAX5959/MAX5960 (1000-up FOB USA).