DFI AL551 Intel Apollo Lake 3.5" SBCs with Dual GbE, Triple Display and Extended Temperature Options

Many HMI and kiosk designs start with the display: an LCD panel behind the bezel, perhaps a second monitor for a supervisor, and a board small enough to sit behind them. The DFI AL551 series puts Intel Apollo Lake processors on a 146 x 102 mm 3.5″ SBC with three independent display outputs, so one board can drive an internal LVDS panel and two external screens.

Every AL551 board takes one DDR3L 1866 MHz SO-DIMM of up to 8 GB, so memory is sized to the application at build. Intel HD Graphics drives VGA at up to 2048 x 1536, DP++ at up to 4096 x 2160 at 60 Hz and dual-channel 48-bit LVDS at up to 1920 x 1200, with triple display support. Audio on a Realtek ALC262 codec provides line-out, mic-in and a speaker output for two 3 W speakers, which suits kiosks and HMIs with audible alerts.

Five builds cover 0 to 60 °C. AL551-BN-E3950 carries the quad-core Atom x7-E3950 at 1.6 to 2.0 GHz and 12 W, AL551-BN-E3940 the quad-core x5-E3940 at 9.5 W and AL551-BN-E3930 the dual-core x5-E3930 at 6.5 W. AL551-BN-N4200 uses the quad-core Pentium N4200, bursting to 2.5 GHz at 6 W, and AL551-BN-N3350 the dual-core Celeron N3350 for simpler terminals. For harsher sites, AL551-EN-E3950 rates the x7-E3950 build for -20 to 70 °C and AL551-TN-E3950 for -40 to 85 °C.

Two GbE ports on Intel I210AT controllers give separate machine and plant networks. USB is two USB 3.1 Gen 1 and two USB 2.0 Type-A ports at the rear and two USB 2.0 on headers. Two RS-232/422/485 COM ports and an 8-bit DIO handle serial devices and machine signals. An M.2 B-key (2242) with PCIe, USB 2.0 and SATA takes an SSD or a module, a full-size Mini PCIe socket takes Wi-Fi, and one SATA port adds a drive.

Power is 12 V DC on a 4-pin or barrel connector, and every board is cooled by a fanless heatsink. The AL551 series carries CE, FCC, UKCA and RoHS compliance, has a firmware TPM 2.0 and a watchdog timer programmable from 1 to 255 seconds and supports Windows 10 IoT Enterprise and Linux. Every build shares the same board layout, so a design qualified on one processor can move to another, or to a wider temperature rating, without changing the enclosure.