Open-source hardware design files for the ProtoCentral ADS1293 3-Channel, 24-bit ECG Breakout — a multi-lead ECG analog front end based on the Texas Instruments ADS1293.
The ADS1293 integrates three simultaneously sampled, 24-bit ECG channels and a fourth analog channel for pace-pulse detection, at 0.3 mW per channel. Right-leg drive, Wilson Central Terminal generation and lead-off detection are all on-chip, so the board carries no discrete instrumentation-amplifier or filter chain — you get a complete ECG signal path over SPI. Two 3.5 mm jacks accept the standard snap-lead electrode cables, and the board runs from either 3.3 V or 5 V on both supply and logic with no jumpers to set.
Don't have one? Buy it here
| 🛒 Product page | https://protocentral.com/product/protocentral-ads1293-breakout-board/ |
| 💻 Arduino library | https://github.com/Protocentral/protocentral-ads1293-arduino |
| 📄 IC datasheet (TI) | https://www.ti.com/lit/ds/symlink/ads1293.pdf |
- AFE: Texas Instruments ADS1293 — 3-channel, 24-bit ECG analog front end
- Channels: three simultaneously sampled 24-bit ECG channels, plus a fourth analog channel for pace-pulse detection
- Power: 0.3 mW per channel
- On-chip: right-leg drive amplifier, Wilson Central Terminal generation, AC and DC lead-off detection
- Electrode inputs: RA, LA, LL, RL, V1 and IN6, brought out across the two 3.5 mm jacks and silkscreened beside each jack contact
- Clock: onboard 4.096 MHz crystal (ECS-41-18-5PXEN);
CLK OUT/INtest pad for driving several boards from one clock - Interface: SPI, via a TXB0108 8-bit bidirectional level translator
- Connectors: 2× 3.5 mm TRS electrode jacks (CON1, CON2), 0.1″ 1×10 header
- Supply: 3.3 V – 5 V on VCC and on logic — no jumper selection; an onboard Toshiba TCR2EF33 LDO derives the internal 3.3 V rail
- Board: 4× plated mounting holes
The 1×10 header, in silkscreen order:
| Pin | Function |
|---|---|
| GND | Ground |
| VCC | Supply, 3.3 V to 5 V |
| ALARM | Alarm / interrupt output |
| SYNC | Multi-board synchronisation |
| RST | Reset, active low |
| CSB | SPI chip select, active low |
| SCK | SPI clock |
| MISO | SPI data out |
| MOSI | SPI data in |
| DRDY | Data-ready output |
Each 3.5 mm TRS jack carries three electrode contacts:
| Jack | Tip | Ring | Sleeve |
|---|---|---|---|
| CON1 | LA — left arm | RA — right arm | RL — right leg (driven reference) |
| CON2 | LL — left leg | IN6 | V1 — chest |
JP2 — silkscreened CONN / IN6 / WCT — ships bridged 1–2, tying the ADS1293's IN6 input to the
Wilson Central Terminal. Cut it and bridge 2–3 to route CON2's ring contact to IN6 instead.
This board has no patient isolation and is not a medical device. When the subject is a person, power the host from a battery — never while it is connected to mains USB. This is a research, education and maker board.
| Folder | Contents |
|---|---|
hardware/v2/ |
Current Rev 2 KiCad project (schematic + PCB layout) and the exported schematic PDF |
hardware/v1/ |
Superseded Rev 1 Eagle sources, kept for reference |
docs/ |
Reference material, including the ADS1293 datasheet |
assets/ |
Product photography used by this README |
Rev 2 (silkscreened v2 08/26) is the current shipping board. Changes from Rev 1:
- Supply and logic both accept 3.3 V – 5 V directly; the Rev 1 logic-level and supply-selection solder jumpers are gone.
- The header is 10 pins and is not pin-compatible with the 12-pin Rev 1 header.
WCTandCLKare no longer brought out to the header, and aSYNCpin has been added.CSis now labelledCSB. CLKmoved to aCLK OUT/INsolder pad.- Electrode assignments are now silkscreened next to the jack contacts they belong to.
- Four plated corner mounting holes, up from two.
- The 3.5 mm jacks moved to the top edge of the board.
The Arduino library is unchanged across the two revisions — it takes DRDY and CS as constructor arguments and uses hardware SPI, so only your wiring differs.
The hardware design files in this repository are licensed under the CERN Open Hardware Licence Version 2 – Permissive (CERN-OHL-P v2). See LICENSE.
The accompanying Arduino library (in the separate protocentral-ads1293-arduino repository) is licensed under the MIT License.