Table 3.

Comparison of state of the art works. SPS, samples per second; ESB, Enhanced ShockBurst.

	This Work	Neurochip-2	WIMAGINE	PennBMBI	W-HERBS	Nguyen	Angotzi
	(2015)	(2011) [9]	(2015) [8]	(2015) [11]	(2011) [7]	(2014) [10]	(2014) [12]
Recording channel	32 unipolar/bipolar	3 unipolar/bipolar	64	4	64×2	32	8
Gain	192	1000 or 5000	1000	200	40–80 dB	200	-
ADC resolution	16 bits	8 bits	12 bits	12bits	12 bits	16 bits	8 bits
Sampling rate	800 SPS/channel up to 30 kSPS/channel	256 SPS	1 kSPS	21 kSPS	1 kSPS	400 kSPS 12.5 kSPS/channel	15 kSPS/channel
Bandwidth	0.1–20 kHz	10 Hz–7.5 Hz	0.5 Hz–400 Hz	0.05 Hz–6 kHz	0.1 Hz–1 kHz	0.2 Hz–5 kHz	1 Hz–10 kHz
Communication	2.4 GHz RF communication link with μESB protocol	Serial cable/ infrared data link	Proprietary UHF link in MICS band	2.4 GHz RF communication link	Bluetooth	Wired	2.4 GHz ISM band
Power supply	Rechargeable 3.7 V battery	1 or 2 rechargeable 3.6 V battery	Inductive link	Rechargeable 3.7 V battery	Polymer Lithium ion 3.7 V battery	5 V USB	3.7 V 700 mAh battery
Power consumption	4.22–15.4 mA	284–420 mW	75 mW w/o charging 350 mW w/ charging	7.3 mA transmit for sensor node only	4.9 mW (AFE) 300 mW (wireless)	-	-
Battery charging	Wireless ultrasonic charging	-	-	-	Wireless charging coil 4 W at distance 38 mm	-	-
Size	35 mm in diameter 10 mm in thickness	63×63×30 mm	50 mm in diameter 12.54 mm in thickness antenna:10 cm${}^2$	56×36×13 mm + 43×27×8 mm + 31×13×8 mm	20×30×2.5 mm + 60×60×8 mm + 40 mm in diameter 8 mm in thickness	29.5×43.4 mm	-
Stimulation channel	4 unipolar/bipolar	3 unipolar/bipolar	-	2	-	1 optical stimuli	8 bipolar
Stimulation voltage	20 V	±15 V (normal) ±50 V (high V)	-	±12 V	-	-	±9 V
current intensity	40 $\mathsf{\mu }$A	10–200 $\mathsf{\mu }$A current pulse or 0.5–5 mA	-	0–1 mA	-	-	300 $\mathsf{\mu }$A
Pulse width	1 us minimum	0.2 ms, 0.6 ms	-	200 $\mathsf{\mu }$s	-	-	-
Pulse frequency	250 Hz	1/min or 1/10 min	-	-	-	-	-