Zettasensing offers a comprehensive smart ring solution for end customers and solution providers, built on our ZSPD4000 series wearable AFE chip. This solution leverages the series' high integration, low power consumption, and high signal-to-noise ratio. Through advanced co-packaging technology that integrates the photodetector (PD), the ZSPD4000 series effectively minimizes the required PCB area.
The accompanying software algorithms enable the monitoring and management of vital signs, including heart rate, blood oxygen, HRV, ECG, and blood pressure.
Solution Advantages
Ultra-Compact Package Size1
The small package size (4.5 x 2.5 x 0.9 mm) offers higher integration and saves space, significantly reducing the circuit board footprint.
Signal-to-Noise Ratio (SNR)
- Green Light: Average PI of ~3.6%, average SNR of ~42dB
- Red Light: Average PI of ~0.2%, average SNR of ~25dB
- Infrared: Average PI of ~0.28%, average SNR of ~28dB
Good performance for green light heart rate measurement can be achieved with a single pulse. For red and infrared blood oxygen measurements, a 4-pulse configuration provides reliable performance.
Ultra-Low Power Consumption2
- Green Light Heart Rate: At a 25Hz sampling rate with a 60mA current (single pulse), the average power consumption is 13µA.
- Red/Infrared Blood Oxygen: At a 50Hz sampling rate with a 35mA current (4 pulses), the average power consumption is 150µA.
Enabling Extended Battery Life for Smart Rings3
Based on a runtime power consumption of 80µA/MHz, the combined sensor power budget is:
- Heart Rate (30s every 1 min): ~1.5mAh per day
- Heart Rate (30s every 10 min): ~0.15mAh per day
- Blood Oxygen (30s every 30 min, discrete): ~0.1mAh per day
- Blood Oxygen (30s every 30 min, integrated): ~0.15mAh per day
- HRV (60s every 60 min): ~0.13mAh per day
Across various usage scenarios, the low power consumption of the ZSPD4000 series ensures extended battery life for smart rings.