Silicon Labs recently announced an optical heart rate-sensing solution for wrist-based heart rate monitoring (HRM) applications. The new Si1144 HRM solution includes a low-power optical sensor module paired with an EFM32 Gecko microcontroller running Silicon Labs’s advanced HRM algorithm. The compact Si1144 sensor module integrates an optical sensor, green LED, an ADC, LED drivers, control logic, and an I2C digital interface, making it a good option for power-sensitive wearables.
The Si1144-AAGX HRM module’s features:
- Accurately senses weak blood flow signals on the wrist
- Choice of two algorithms to support static HRM and optional dynamic motion-compensated HRM using data from an external accelerometer
- HRM solution pairs optical module with a Pearl Gecko microcontroller
- Fully integrated HRM IC with green LED lens, high-sensitivity photodiode, low-noise ADC, LED drivers, optical blocking, and host communications/interrupts
- Two LED drivers
- Ultra-low-power consumption for long battery life (less than 500 nA standby current with 1.71-to-3.6-V supply voltage)
- I2C serial communications, up to 3.4-Mbps data rate
- 10-lead 4.9 × 2.85 × 1.2 mm LGA module package
Samples and production quantities of the Si1144-AAGX HRM module currently available. The Si1144 module along with Silicon Labs’s HRM algorithm costs $2.82 in 10,000-unit quantities. The HRM44-GGG-PS development board costs $57.60.
Source: Silicon Labs