TABLE I.
Comparison and Summary
| [19] | [16] | [24] | [25] | [11] | [12], [13] | This work | |
|---|---|---|---|---|---|---|---|
| Application target | Peripheral nerve | Cortex | Cortex | Spinal cord (pain reduction) | Spinal cord (motor function) | Spinal cord (motor function) | Spinal cord (motor function) |
| No. of stim. ch. | 4 | 10 | 8 | 4 | 13 | 4 | 160c, 40d, 20e |
| Stim. mode | Current | Current | Current | Voltage | Current | Current | Current |
| Max current (mA)/resolution (bit) | 25/10 | 4.18/6 | 0.23/5 | 10.5Va/8 | 1/8 | 10/14 |
0.5/7c 2/9d 4/10e |
| Stim. freq. (Hz)/PW (ms) | 0.15–8.3k/0.01–12.8 | 15.4/1 (fixed) | 60–220/0.04–0.44 | 2–150/0.06–0.45 | Any, externally defined | N/A (0.05–2) | Up-to 20k/0.01–8 |
| Residual charge removal | No recording design | N/A | N/A | N/A | N/A | N/A | Yes (passive) |
| No. of recording ch. | 4 | 8 | 1 (FSCV recording) | 16 | |||
| Gain (dB)/BW (Hz) | 54/0.64–6k | 60–74/0.5–3K | N/A | 40–62/5–7k | |||
| ADC ENoB (bit) | 8 | 6.5 | 10 | 8.5 | |||
| Noise (μV)/NEF/power (μW/Ch.) | 6.3/3.76/16 | 1.97/2.9/8.6 | N/A | 7.68/7.64/5.4 | |||
| Duplex data link | N/A | N/A | N/Ab | N/A | Yes (bluetooth) | Yes | |
| Forward data rate | N/A | 0.1 | 0.1 | N/A | ~0.23 | 2 (DPSK) | |
| Reverse data rate | 0.175 | 0.8 | 2 | 0.0002 | ~0.23 | 2 (LSK) | |
| Impedance characterization | N/A | N/A | N/A | N/A | N/A | 48 Ch. | |
| Power telemetry | Yes | Yes | Yes | N/A | N/A | Yes | |
| Stimulator compliance voltage (V) | > 10 | 5 | 4.5 | >10 | 25 | > 5 | ±6 – ±12 |
| CMOS process (nm) | 800 HV | 180 | 180 | 180 | 180 HV | Discrete components | 180 HV |
| Power consumption (mW) | N/A | 0.468 | N/A | ~58.08 | 0.114 | N/A | ~18 |
| Chip size (mm2) | 50 | 4 | 7.5 | 2.4 | 6.4 | N/A | 29.5 |
| Implant size (cm3)/weight (g) | 3/6 | N/A | N/A | N/A | N/A | N/A | 0.5/0.7 |
a
[25] only supports voltage-mode stimulation.
b
Stimulation parameters must be programmed before starting wireless recording.
c,d,e
Multiple stimulator outputs can be combined to support large stimulation current.