
Analog Devices Inc. ADPD4000 & ADPD4001 Multimodal Sensor Front End
Analog Devices Inc. ADPD4000 and ADPD4001 Multimodal Sensor Front End can stimulate up to eight LEDs and measure the return signal on up to eight separate current inputs. Twelve available time slots can enable 12 separate measurements per sampling period. The data output and functional configuration utilize an I2C interface on the ADPD4001 or a serial port interface (SPI) on the ADPD4000. The control circuitry includes flexible LED signaling and synchronous detection. The devices use a 1.8V analog core and 1.8V/3.3V compatible digital input/output (I/O).Features
- 8 input channels with multiple operation modes to accommodate the following measurements: PPG, ECG, EDA, impedance, and temperature
- Dual channel processing with simultaneous sampling
- 12 programmable time slots for synchronized sensor measurements
- Flexible input multiplexing to support differential and single-ended sensor measurements
- 8 LED drivers, 4 of which can be driven simultaneously
- On-chip digital filtering
- Flexible sampling rate from 0.004Hz to 9kHz using internal oscillators
- SNR of transmit and receive signal chain: 90dB
- Ambient light rejection: 60dB up to 1kHz
- 400mA total LED drive current
- Total system power dissipation: 50µW (combined LED and AFE power), continuous PPG measurement at 75dB SNR, 25Hz ODR, 100nA/mA CTR
- SPI and I2C communications supported
- 256-byte FIFO
Applications
- Wearable health and fitness monitors: heart rate monitors (HRMs), heart rate variability (HRV), stress, blood pressure estimation, SpO2, hydration, body composition
- Industrial monitoring: CO, CO2, smoke, and aerosol detection
- Home patient monitoring
Block Diagram

Additional Resources
Condition-Based Monitoring of the Human Body
With advances in technology, vital sign monitoring will become increasingly common in various industries and throughout our daily lives. Whether used for treatment or prevention, such health-related solutions call for reliable and robust technology.
Learn More
Vital Signs Monitoring Is Easier Than Ever Before
The health information generated by the wearable devices can play an essential role in health and disease management. With the groundbreaking analog front end (AFE) from Analog Devices, the ADPD4100/ADPD4101,demonstrates it’s never been simpler.
Published: 2019-08-05
| Updated: 2022-03-11