Bidirectional Neural Interface
This device is an implantable neural stimulation and recording system designed for small animal in-vivoneuroscience. It is composed of two modules: the stimulation and recording system, and an external coil for wireless powering. Data transfer is carried out using a bluetooth SoC. Both modules are encapsulated in silicone. The stimulation module features an Omnetics connector to interface with multi-channel recording and stimulation electrodes. This interface can be encapsulated using fast-cure silicones in-situ during an experiment.
The purpose of this tool is to provide a versatile in-vivo experimental platform for peripheral neuroscience. Thanks to wireless powering the system can be used in studies using awake-behaving animals. A backpack with battery and wireless emitter or similar power source can be used to power the implantable interface.
A block diagram of the system is shown on the right. The interface can carry out both stimulation and recording using a custom ASIC. Commands and data sent to and from the ASIC pass through an ICE5LP-4K FPGA to a NRF52832 bluetooth-enabled microcontroller. Both the microcontroller and FPGA are reprogrammable over-the-air giving users improved flexibility over device functions and operation even after chronic in-vivoimplantation.
There are 32 recording and stimulation channels available on the ASIC, allowing for both simple and complex multi-electrode experimental setups. The chip was implemented in a high-voltage CMOS technology to increase voltage compliance. A regulated cascode output stage ensures high output resistance for the stimulator current source.
|Resolution||10-bit||Voltage compliance||±9.25 V|
|Gain||225 - 4725||Current range||6.3-315μA|
|Sampling rate||16kHz||Current resolution||6-bit|