ADPD4000 Multimodal Sensor Front End

Product Highlights > ADPD4000 Multimodal Sensor Front End

            ADPD4000 Multimodal Sensor Front End
                    Analog Devices' sensor has 12 time-slots, enabling 12 separate measurements per sampling period
    

Image of Analog Devices' ADPD4000 Multimodal Sensor Front End Analog Devices' ADPD4000 and ADPD4001 devices operate as a complete multimodal sensor front end by stimulating up to eight LEDs and measuring the return signal on up to eight separate current inputs. Twelve time-slots are available, enabling twelve 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 1.8 V analog core and 1.8 V / 3.3 V compatible digital input/output (I/O).

The analog front end (AFE) rejects signal offsets and corruption from asynchronous modulated interference, typically from ambient light, eliminating the need for optical filters or externally controlled dc cancellation circuitry. Multiple operating modes are provided, enabling the ADPD4000/ADPD4001 to be a sensor hub for synchronous measurements of photodiodes, biopotential electrodes, resistance, capacitance, and temperature sensors.

The ADPD4000 and ADPD4001 are available in a 3.11 mm × 2.14 mm, 0.4 mm pitch, 33-ball WLCSP and 35-ball WLCSP.

Features

Flexible sampling rate from 0.004 Hz to 9 kHz using internal oscillators
On-chip digital filtering
SNR of transmit-and-receive signal chain: 90 dB
Ambient light rejection: 60 dB up to 1 kHz
400 mA total LED drive current
Total system power dissipation: 50 µW (combined LED and AFE power), continuous PPG measurement at 75 dB SNR, 25 Hz ODR, 100 nA/mA CTR
SPI and I²C communications supported
256-byte FIFO

Multimodal analog front end
- Eight input channels with multiple operation modes to accommodate the following measurements: PPG, ECG, EDA, impedance, and temperature
- Dual-channel processing with simultaneous sampling
- Twelve programmable time-slots for synchronized sensor measurements
- Flexible input multiplexing to support differential and single-ended sensor measurements
- Eight LED drivers, four of which can be driven simultaneously

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