DTPlug is an extension box for DomoTab intended to provide a bridge between the tablet versions and wired networks.


Originally planned as a simple extension card to be integrated in the tablet’s power supply, we finally decided to make DTPlug a stand alone product. Like DomoTab, this is a modular product that can be used independently, uses the same module format and an ARM Cortex-M3 micro-controller,NXP‘s LPC1764.

While the LPC1764 doesn’t have a lot of memory (128KB of flash memory, 32KB of SRAM), it has enough to control an IP stack (such as lwip), a mini OS (such as CoOS) and all connected modules.

On top of its Ethernet 10/100 Mbps, USB Device port and SD card slot (to store temperature readings or read configuration data for instance), DTPlug has 4 UEXT extension ports (two of which have extra GPIOs) and a PLC port (power line communication).

In order to fulfil its primary function (power or recharge the DomoTab tablet), DTPlug includes a MeanWell EPS-35-5 Power supply which can provide 30W of useful load, shared between the USB charge sockets. When used with our custom USB charge cable, DTPlug can provide up to 5A of charging current, as defined by USB Battery Charging Specifications (be aware that D+ and D- signals aren’t connected on those two ports).

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