Abstract
This paper reports on design and develo pment of a reliable, single-chip, multichannel wireless biotelemetry microsystem intended for extra cellular neural recording from awake, and behaving small animal models. The s ystem re- quirements for reliable neural recording are identi fied and the inherently con flicting requirements of low power and re- liability are addressed at architectu ral and circuit levels. The 2.85 3.84 mm , mixed-signal ASIC is fabricated in a 0.5 m 2P3M n-well standard CMOS process; and integrates a low-noise front-end, programmable digital c ontroller, an RF modulator, and an RF power ampli fier at the ISM band of 433 MHz on a single-chip. The microsystem, i ncorporating the ASIC, features 9-channel, is programmable, weighs 2.2 g (including batteries) and h a sd i m e n s i o n so f2 . 2 1.1 0.5 cm . The transmitter consumes 5 mW and has a measured input referred voltage noise of 4.58 ,6 . 2 0 , and 7.81 at tr ansmission distances of 3 m, 10 m, and 20 m, respectively . The measured inter-channel crosstalk is less than 3.5% and battery life is about an hour. The presented biotelemetry system has been successfully used in two in-vivo neural recording experiments: i) from the antennas of a freely roaming South-America n cockroach, and ii) from the hippocampus of an awa ke and mobile rat.