Implantable Pulse Generator — Gen2 PCBA¶
Repo: CARSSCenter/OpenNerve-Implantable-Pulse-Generator · Gen2 PCBA/ and Docs/
Not approved for human use
Nothing described on this page has regulatory clearance for human use. See Regulatory status and disclaimers.
Maturity¶
Evidence E2 Acute in vivo
Manufacturing readiness M2 Manufacturable by most PCBA vendors
See Maturity level definitions for more information.
Standing disclaimer
These levels describe testing history and documentation state. They are not regulatory clearance and not a safety endorsement.
About the Gen2 PCBA¶
The Gen2 PCBA has two fully independent bipolar stimulation channels (also configurable as four monopolar stim channels), capable of square-wave stimulation up to 1200 Hz or low-frequency sine-wave stimulation, four configurable analog front ends (AFEs) for biosignal recording, and one I2C port for third-party digital sensors. (source)
Two microcontrollers are used, shared with Gen1: an nRF52810 for BLE
(FW-BLE/, same firmware across both revisions) and an STM32U5 for stimulation,
sensing, and system control (Gen2 PCBA/FW-MCU-H2/, revision-specific).
For how Gen2 compares to Gen1, see the IPG overview.
This is the PCB revision used in the development board — the same electronics, kept in its manufacturing frame for bench use instead of being trimmed down for implantation. The specifications below apply to both.
Specifications¶
Stimulation and AFE (analog front end) specifications for the Gen2 PCBA, as sourced in the OpenNerve IPG flyer (internal document, not yet published to a public repo — see the note below).
Stimulation parameters¶
| Stimulation parameter | Minimum | Maximum | Step |
|---|---|---|---|
| Amplitude, mA | 0.2 | 5 | 0.1 |
| Pulse width, µs | 100 | 800 | 50 |
| Frequency, Hz | 1 | 1200 | 1 |
| Output limits, V | 0 | 11 | — |
| Ramp up/down duration, s | 0 | 10 | 1 |
| Train on/off duration, s | 10 | 300 | 10 |
AFE specifications¶
| AFE specification | ECG HR | ECG RR | eCAP | EMG |
|---|---|---|---|---|
| High-pass filter, Hz | 0.5 | 0.09 | 7.97 | 0.4 |
| Low-pass filter, Hz | 83.8 | 0.73 | 1,750 | 665 |
| Amplitude min LSB, ±µV | 2.8 | 2.8 | 0.37 | 1.4 |
| Amplitude max at 14 bit, ±mV | 24 | 24 | 3 | 48 |
| Gain for ADC Vref = ±3V | 125 | 117 | 1,005 | 250 |
| Recommended ADC freq., Hz | 256 | 256 | 6,400 | 2,560 |
ECG: electrocardiography. RR: respiratory rate. eCAP: evoked compound action potential.
Design outputs and BOM/fab notes¶
| File | Format | Path | Covers |
|---|---|---|---|
| Schematic + layout | Gen2 PCBA/IPG-schematic-layout.PDF |
Schematic and layout combined in a single document | |
| Bill of materials | XLSX | Gen2 PCBA/IPG-BOM.xlsx |
Component list |
| 3D model | STEP | Gen2 PCBA/IPG.step |
Board mechanical outline |
| Altium project | Altium .PrjPcb/.PcbDoc |
Gen2 PCBA/PCBA-Altium/ |
Editable schematic/layout source (IPG.PcbDoc, IPG_Rigid.PcbDoc, 15 sheet .SchDoc files, HORNET-IPG.IntLib component library) |
| MCU firmware image | .hex (also .bin) |
Gen2 PCBA/FW-MCU-H2/ |
Most recent built firmware image; source under FW-NIH-MCU-H2/ |
The enclosure is shared across both PCB revisions and versioned independently
(current rev 0.7):
12mm IPG model.STEP/.STL,
8383, 12mm IPG, Rev 0.7.STEP,
design file set PDF.
Documentation¶
Gen2 PCBA design files¶
The schematic and layout PDF in Gen2 PCBA/, embedded below:
Schematic + layout
Firmware Design Documentation¶
CAR-206 IPG SAD.pdf
CAR-207 IPG SDS.pdf
CAR-211-VVT.pdf
Firmware and software¶
- MCU firmware (
Gen2 PCBA/FW-MCU-H2/) is specific to this revision — do not carry over Gen1 MCU firmware claims. See the MCU flashing guide. - BLE firmware (
FW-BLE/) is shared with Gen1. See the BLE flashing guide. - Control software (Windows now, Android in development) is the same across both revisions — see Software.