PCI Express Mini Card
PCI Express Mini Card (also known as Mini PCI Express, Mini PCIe, Mini PCI-E, mPCIe, and PEM), based on PCI Express, is a replacement for the Mini PCI form factor. It is developed by the PCI-SIG. The host device supports both PCI Express and USB 2.0 connectivity, and each card may use either standard. Most laptop computers built after 2005 use PCI Express for expansion cards; however, as of 2015, many vendors are moving toward using the newer M.2 form factor for this purpose.
Due to different dimensions, PCI Express Mini Cards are not physically compatible with standard full-size PCI Express slots; however, passive adapters exist that allow them to be used in full-size slots.
Dimensions of PCI Express Mini Cards are 30 × 50.95 mm (width × length) for a Full Mini Card. There is a 52-pin edge connector, consisting of two staggered rows on a 0.8 mm pitch. Each row has eight contacts, a gap equivalent to four contacts, then a further 18 contacts. Boards have a thickness of 1.0 mm, excluding the components. A "Half Mini Card" (sometimes abbreviated as HMC) is also specified, having approximately half the physical length of 26.8 mm.
PCI Express Mini Card edge connectors provide multiple connections and buses:
- PCI Express ×1
- USB 2.0
- Wires to diagnostics LEDs for wireless network (i.e., Wi-Fi) status on computer's chassis
- SIM card for GSM and WCDMA applications (UIM signals on spec.).
- Future extension for another PCIe lane
- 1.5 V and 3.3 V power