Sense.HR
Betaheart rate, pulse oximetry, and hydration
The fully-integrated Sense.HR optical heart-rate and SpO₂ sensor combines the advanced Analog Devices MAX86174A photoplethysmography (PPG) front end with dual Vishay VEMD1060X01 silicon PIN photodiodes and four LEDs (two green, one red, one IR) for multi-wavelength reflective optical sensing. The 20-bit ADC with a 256-word FIFO provides data at configurable rates from 1 to 2048 frames per second for external processing.

Technical Summary
- Package
- T44-10
- Drawing
- Land pattern (PDF)
- Packaging
- 12mm tape and reel (drawing)
- Power
- 1.8V (system)2.7–5.5V (system)
- Interfaces
- I2CSPI
Resources & Links
- Datasheet
- Coming soon
- JSON Tile Definition
- v0.10 (Aug 11, 2026)
- Drivers
- Documentation|GitHub
- Discussion
- Discord
Configuration
- I2C address
- 0xD5 (default)0xD6 (alternate)
- Interface mode
- I²CSPI (4-wire)
Pad Assignments
| Pad | Type | Function | Note | |
|---|---|---|---|---|
| 1 | ⏻ | GND | ||
| 2 | D | I2C.AD0 | internal pull-up sets the default I2C address to 0xD6; connect to GND to switch to 0xD5; do not connect > 2.0V | |
| D | SPI.MISO | |||
| 3 | D | I2C.EN | internal pull-up enables I2C by default; connect to GND to switch to SPI; do not connect > 2.0V | |
| D | SPI.CS | 6V tolerant | ||
| 4 | D | I2C.CLK | 6V tolerant | |
| D | SPI.CLK | 6V tolerant | ||
| 5 | D | I2C.DAT | 6V tolerant | |
| D | SPI.MOSI | 6V tolerant | ||
| 6 | — | |||
| 7 | — | |||
| 8 | D | INTB | configurable interrupt output | |
| 9 | ⏻ | VLED | 2.7-5.5V | |
| 10 | ⏻ | V+ | 1.8V |
I2C
I2C- Mode
- slave
- Max Clock
- 400kHz
- Addresses
- 0xD5(default), 0xD6
- Format
- 7-bit address
| Function | Required | Pad(s) |
|---|---|---|
| I2C.CLK | Yes | 4 |
| I2C.DAT | Yes | 5 |
SPI
SPI- Mode
- slave
- Max Clock
- 20MHz
- Address
- —
- Format
- —
| Function | Required | Pad(s) |
|---|---|---|
| SPI.MISO | No | 2 |
| SPI.CS | No | 3 |
| SPI.CLK | No | 4 |
| SPI.MOSI | No | 5 |
Development Product — This is an electronic development module intended for evaluation, prototyping, and integration into other designs by qualified engineers and developers. It is not a finished consumer product and has not been independently certified for FCC, CE, UL, or other regulatory compliance. The integrator of this module into a finished product is responsible for obtaining all necessary certifications. Not intended for use in life-support systems, safety-critical applications, or any application where failure could result in personal injury or property damage.

