standard defines a small form factor card for I/O expansion
In computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world, possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
of embedded systems and other space-constrained computing applications. The cards are intended to be used for adding a wide range of capabilities, such as A/D
An analog-to-digital converter is a device that converts a continuous quantity to a discrete time digital representation. An ADC may also provide an isolated measurement...
In electronics, a digital-to-analog converter is a device that converts a digital code to an analog signal . An analog-to-digital converter performs the reverse operation...
, digital I/O, counter/timers, serial I/O, wired
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
A wireless local area network links two or more devices using some wireless distribution method , and usually providing a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network...
networking, image processing
In electrical engineering and computer science, image processing is any form of signal processing for which the input is an image, such as a photograph or video frame; the output of image processing may be either an image or, a set of characteristics or parameters related to the image...
, GPS, etc. to their host systems.
FeaturePak cards plug into edgecard sockets, parallel to the mainboard, similarly to how SO-DIMM memory modules install in laptop or desktop PCs.
The FeaturePak socket consists of a 230-pin "MXM"
A Mobile PCI Express Module is an interconnect standard for GPUs in laptops using PCI Express created by MXM-SIG...
connector, which provides all connections to the FeaturePak card, including the host interface, external I/O signals, and power. (Note, however, that the FeaturePak specification's use of the MXM connector differs from that of Nvidia's MXM specification.)
Host interface connections include:
- PCI Express
PCI Express , officially abbreviated as PCIe, is a computer expansion card standard designed to replace the older PCI, PCI-X, and AGP bus standards...
-- up to two PCI Express x1 lanes
- USB -- up to two USB 1.1 or 2.0 channels
- Serial—one logic-level UART interface
Joint Test Action Group is the common name for what was later standardized as the IEEE 1149.1 Standard Test Access Port and Boundary-Scan Architecture. It was initially devised for testing printed circuit boards using boundary scan and is still widely used for this application.Today JTAG is also...
- PCI Express Reset
- Several auxiliary signals
- 3V and 5V power and ground
- Reserved lines (for future enhancements)
The balance of the 230-pin FeaturePak socket is allocated to I/O, in two groups:
- Primary I/O—50 general purpose I/O lines, of which 34 pairs have enhanced isolation
- Secondary I/O—50 general purpose I/O lines
The FeaturePak socket's MXM connector is claimed capable of 2.5 Gbit/s bandwidth on each pin, thereby supporting high-speed interfaces such as PCI Express, gigabit Ethernet, USB 2.0, among others. Enhanced I/O signal isolation within the Primary I/O group is accomplished by leaving alternate pins on the MXM connector interface unused.
FeaturePak cards are powered by 3.3V and use standard 3.3V logic level
In digital circuits, a logic level is one of a finite number of states that a signal can have. Logic levels are usually represented by the voltage difference between the signal and ground , although other standards exist...
s. The socket also provides a 5V input option, for cards that require the additional voltage to power auxiliary functions.
Other than the provision of extra isolation for 34 signal pairs, there is no defined allocation of the signals within the Primary I/O and Secondary I/O groups, leaving each FeaturePak to define its own utilization of the I/O signals. Consequently, there is little limitation as to what can be implemented on a FeaturePak card.
Overall FeaturePak horizontal dimensions are 1.75 x 2.55 inches (43 x 65 mm). There are two options for topside component thickness: "tall" FeaturePak modules may have topside components of up to 0.4 inch (10 mm) thick; "standard" modules are limited to 0.19 inch (4.8 mm) topside component thickness.
The FeaturePak standard was launched by the FeaturePak Initiative at Embedded World 2010 in Nuremberg, Germany, in March 2010. At launch, the Initiative consisted of FeaturePak originator Diamond Systems
, plus FeaturePak Initiative charter members Arbor Technology
, Cogent Computer Systems
, Connect Tech
, Douglas Electronics
, and IXXAT Automation
The FeaturePak Initiative subsequently was superseded by a California nonprofit corporation known as the FeaturePak Trade Association (FPTA), which assumed ownership of the FeaturePak specification and other IP (intellectual property) and became responsible for maintaining, extending, and promoting the FeaturePak standard and established restrictions and guidelines pertaining to the use of the FeaturePak trademark and logos.
The FeaturePak specification is freely available by application on the FeaturePak Trade Association's website. As stated on FeaturePak.org, "You need not join the FPTA or be otherwise licensed, in order to develop or manufacture products based on or incorporating FPTA specifications. However, use of FPTA-owned logos is restricted to FPTA members in good standing or to those explicitly licensed by the FPTA to use them. Please contact the FPTA for details regarding non-member licensing of FPTA logos."