DFI ALF51-TN-46E40 Intel Apollo Lake Atom x5-E3940 Femto-ITX Single Board Computer with Dual GbE and Extended Temperature

An outdoor gateway that buffers data during a network outage, runs a VPN and hosts remote management tools needs more memory than a simple logger, and it still has to start at -40 °C. The ALF51-TN-46E40 is a 1.8″ Femto-ITX single board computer in the DFI ALF51 series that pairs 4 GB of memory with the quad-core Atom and a -40 to 85 °C rating.

The Intel Atom x5-E3940 has four Apollo Lake cores at 1.6 GHz with a 1.8 GHz burst and a 9.5 W TDP. Its 4 GB of single-channel LPDDR4 at 2400 MHz and 64 GB of eMMC are soldered down, which avoids memory and storage sockets that can loosen under vibration. Intel HD Graphics drives a DP++ output at up to 4096 x 2160 at 60 Hz. DFI lists Windows 10 IoT Enterprise 64-bit and Linux support with UEFI boot, alongside a firmware TPM 2.0 and a watchdog timer.

Two GbE ports on Intel I210 controllers can split a camera or sensor network from the uplink. Two USB 3.1 Gen 1 Type-A ports and a USB 2.0 header connect a modem or storage, an RS-232/422/485 header links controllers and meters, and an 8-bit DIO header monitors tamper switches or drives outputs. A full-size mini PCIe socket takes a wireless module.

The ALF51-TN-46E40 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-86E40 moves to 8 GB at the same rating, and the ALF51-TN-26E40 keeps 2 GB where the workload is lighter, such as a single protocol converter or logger.