Table 1.
Summary of specifications of the iTDS-2 and benchmarking with other intraoral tongue-operated ATs [12,14,17].
| Specifications | iTDS-2 | iTDS-1 [12] | ITCS [17] | Optical Tongue Gesture [14] | |
|---|---|---|---|---|---|
| Process | 0.35-μm std. CMOS | 0.5-μm std. CMOS | Off-the-shelf | Off-the-shelf | |
| Die Area | 2.4 × 5.0 (mm2) | 3.8 × 3.7 (mm2) | - | - | |
| VDD | 1.8 (V) | 1.8 (V) | - | - | |
| Sensor | Type | Magnetoresistive | Magnetoresistive | Inductive | Infrared proximity |
| Channel | 12 | 12 | 18 | 4 | |
| Sensitivity | 1.8 (mV/gauss) | 1.8 (mV/gauss) | - | 0.2–0.5 (V/mm) | |
| Sampling | 64 (Hz) | 64 (Hz) | 30 (Hz) | 90 (Hz) | |
| RF | Frequency Band | 27/432 (MHz) | 27/432 (MHz) | 2.4 (GHz) | Hardwired |
| Switching between Bands | Automatic | Manual | Single band | ||
| Data rate | 250 (kbps) | 64 (kbps) | - | ||
| Power | Pavr (27 MHz) | 2.8 (mW) | 3.7 (mW) | - | Hardwired |
| Pavr (432 MHz) | 3.3 (mW) | 4.7 (mW) | |||
| Battery Type | Li-Ion 50 mAh | Li-Ion 45 mAh | Li-Ion 20 mAh | ||
| Battery Lifetime | 27.3 (h), worst case | 17.2 (h), worst case | 15 (h) | ||
| Prototype | Shape | Arch shape | Palatal shape | Palatal shape | Palatal shape |
| Size | 54 × 28 × 15 (mm3) | 49 × 42 × 15 (mm3) | 35 × 25 × 15 (mm3) * | 41 × 38 × 15 (mm3) * | |
| Volume | 12 (mL) | 20 (mL) | - | - | |
| Weight | 30 (g) | 75 (g) | - | - | |
*
Estimated from publication.