Form factor
For components and devices in engineering, principally electronic, a form factor defines the linear dimensions, mounting and connector standards, and other parameters that categorize the item as belonging to a mechanically compatible family. For example, personal computer motherboards come in form factors defined by such things as ATX, and PC towers are in micro, mini, and full size form factors. Peripheral component cards are in one of several PCI[1] form factors, with the "half-length" having become the most common.
Rack mounting
In the general electronics industry, "rack mountable" devices are 19 inches/482.6 mm wide and some multiple of 1.75 inches/44.45 mm tall, with mounting flanges protruding from the front.
The flanges have holes through which standard mounting screws go into pre-tapped holes in a mounting rail on both sides of the device.[2]The mounting rails have a width 0.625 inches/15.875 mm wide, separated by 17.75 inches/450.85 mm, giving the total 19 inch width. Mounting rails are paired, such that each hole is separated, center-to-center, by 18.3 inches/464.82 mm.
Joint Tactical Radio System: form factor reduction
The Joint Tactical Radio System (JTRS) is a radical simplification of different form factors used by U.S. military electronics, primarily radios and encryption devices. JTRS is a software defined radio, in which many of the discrete electronic components, and even fundamental techniques such as superheterodyne operation, are replaced by computer-controlled digital signal processors.[3] 26 different form factors were identified as being in military use, and, with the smaller size and programmability of the JTRS architecture, reduced to 13 form factors:
- Manpack
- Handheld
- Airborne, Maritime and Fixed Site Small Airborne (AMF-SA)
- AMF-MF (Maritime/fixed site)
- Small form factor (SFF) A&H (for Intelligent Munitions Systems and Unattended Ground Sensors (UGS) in the Future Combat System(FCS))
- SFF B, C and I (for Ground Soldier Systems)
- SFF D (for aerial systems)
- SFF J (for Networked Missile Launcher System in FCS)
Mobile telephones
Cases for cellular telephones and physically compatible electronics come in several form factors:[4]
- Bar
- Clamshell or folder
- Flip
- Slide
- Swivel:
References
- ↑ Peripheral Component Interconnect Special Interest Group
- ↑ Electronics Industries Association standard 310-D, International Electrotechnical Commission standard 60297
- ↑ Joint Program Executive Office, Joint Tactical Radio System
- ↑ "Form Factor", Phone Scoop