Dual Port Support for PCIe®
The PCI Express® (PCIe® ) interface may be configured as either a Single port x4 lane SSD or a Dual port x2 lane SSD. If the dual port control signal, called DualPortEn# (Pin 46), is enabled by the host then the NGSFF SSD works as a Dual port x2 lane mode to provide High Availability, which is needed by many enterprise server systems.
Gen-Z Interface Support
Gen-Z supports a wide range of physical layer signaling rates and types, including both electrical and optical. NGSFF SSDs may support Gen-Z devices that utilize the PCIe® physical layer. The Gen-Z device appears to the system as a PCIe® device before and during training.
12V Direct Main Power and 3.3V Aux Power
The NGSFF supports 12V as the main power source (Pin 30, 32, 34, 36) to the SSD. Therefore, the host does not need to convert from 12V to 3.3V voltage in the host system, so the number of voltage regulator chips on the host system PCB is reduced. This decreases the complexity of the PCB and software while lowering the BOM cost as well.
Power Reset of NGSFF SSD by Software
NGSFF supports a “Power Disable” control signal, called PWDIS (Pin 28), which disables 12V power to all of the active components on the NGSFF SSD. This PWDIS functionality is applied only to the 12V supply, and does not affect the 3.3V supply. This power disable capability allows for easier remote power reset of SSD by software.
Hot-Plug Insertion and Removal and Host-Side Implementation
To support hot-insertion and hot-removal of the NGSFF SSD, the two presence detect signals--PRSNT 1# (pin 67) and PRSNT 2# (pin 6)—are defined. These presence detect signals are used by the system to recognize the presence of an NGSFF SSD in order to enable auxiliary signals like the reference clock, PCIe® reset, and SMBus signals.