DFI ALF51-TN-26E40 Intel Apollo Lake Atom x5-E3940 Femto-ITX Single Board Computer with Dual GbE and -40 to 85 °C

Trackside cabinets, roadside units and equipment on vehicles can see frost at night and direct sun by day, and the board inside has to start and run at both ends. The ALF51-TN-26E40 is a 1.8″ Femto-ITX single board computer in the DFI ALF51 series rated from -40 to 85 °C, with four Intel Atom cores and no fan to fail.

The Intel Atom x5-E3940 is a quad-core Apollo Lake processor at 1.6 GHz with a 1.8 GHz burst and a 9.5 W TDP, enough to run data collection, a small database and remote access at once. It carries 2 GB of LPDDR4 at 2400 MHz soldered down and 64 GB of eMMC, and Intel HD Graphics drives a DP++ output at up to 4096 x 2160 at 60 Hz. DFI supports Windows 10 IoT Enterprise 64-bit and Linux with UEFI boot, with a firmware TPM 2.0 and a watchdog timer.

Two GbE ports on Intel I210 controllers can link cameras or field devices on one side and the backhaul on the other. Two USB 3.1 Gen 1 Type-A ports and a USB 2.0 header add storage or a modem, an RS-232/422/485 header connects older equipment, and an 8-bit DIO header monitors door contacts or switches outputs. The full-size mini PCIe socket takes a Wi-Fi module over PCIe or USB 2.0.

The ALF51-TN-26E40 runs from 12 V DC on a terminal block and cools passively across -40 to 85 °C, with CE, FCC and RoHS compliance. The ALF51-TN-46E40 and ALF51-TN-86E40 keep this rating with 4 or 8 GB of memory, and the ALF51-TN-26E30 uses the 6.5 W dual-core Atom x5-E3930 where power is tighter.