Cube K8

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The Cube K8 is a tablet which is commercially available for $89 (plus $30 S&H).

Overview

The Cube K8 provides an ARM processor w. 512MB of memory and 8GB of eMMC storage. No Cube. No Funny.

Display

The display size is 7" diagonal w. 16:9 aspect ratio. The resolution is 800 x 480.

A multitouch capacitive touchscreen is integrated. The technology is film/glass/film, which is an unusual one. This results in a capacitive touchscreen in which the outer surface is PET (plastic), not glass. The screen surface can be scratched quite easily --- a clear protective cover is provided with the tablet when purchased. Unlike most capacitive touchscreens, the controller IC (Goodix GT801) for the touchscreen is located on the motherboard, not the flex cable connecting the touchscreen to the motherboard.

There is one internal speaker and an internal mono microphone.

Connectivity

The Cube K8 has 802.11b/g WiFi using an antenna on the motherboard.

Location/Movement

The Cube K8 has an accelerometer.

Ports

  • One mini USB
  • One full-size type A USB
  • One microSD card, externally accessible
  • One DC input port
  • One stereo Headphone Jack (3.5mm)

There is one button on the front panel, and three buttons (power, ESC, and M) along one side.

There is one attached flap covering the microSD slot, and another covering the USB and power ports. The flap covering the power ports interferes with insertion of the DC power adapter.

Power

The Cube K8 has a 11Wh Li-Ion polymer battery (3.7V @ 3000mAh).

There are two wires to the battery, soldered directly to the main motherboard. The battery is soft-sided.

While the unit is labelled 5V 2000 mA on the back cover, the supplied power adapter is only rated for 5V 1500 mA! Actual power draw when starting to charge the battery is only around 1.1A at 5V, so the charger is sufficient. It takes greater than four hours to fully charge the battery.

Breakdown

The bezel and back cover snap together, with no screws. With the exception of the speaker, which fits into a niche in the back cover, everything is assembled into the bezel. The motherboard is held in place with three small self-tapping screws. The touchscreen is adhered to the display, and the display sandwich is help in places with plastic catches around the bezel.

All flex cable connectors (display, touchscreen, front panel button) were glued shut after assembly.

Height

The tablet thickness is roughly 13.3mm in the middle. The height stackup is:

Height Stackup
Front bezel: 1.4mm
Touchscreen: 1.1mm
Air Gap: 0.6mm
Display: 3.8mm
Motherboard: 4.6mm Battery: 4.5mm
Air Gap: 0.4mm
Back plastic: 1.5mm

Weight

The tablet weight is roughly 326 grams. This breaks down as:

Weight
Cover Glass/Touchscreen/Display 156g
Motherboard/Speaker: 40g
Battery: 68g
Back cover/Bezel: 62g
Total: 326g

BOM

Another breakdown is at: Slate4Sure, for the K8GT model which includes a camera. It is the same motherboard and case.