New Content (2)
Technical ArticlesOptical Heart Rate Measurement at the Earbud
Features and Benefits
2.8 mm × 5.0 mm module with integrated optical components
- 660 nm LED, 880 nm IR LED, and photodiode
- Fully integrated AFE, ADC, LED drivers, and timing core
- Custom optical package for use under a glass window
- Programmable 2-channel, 8.5 mA to 370 mA LED drivers
- Provision to use external LED emitters
- Low power
- Specifically designed for ultralow direct optical reflections
- Independent AFE settings per channel
- I2C data and control interface
- Burst accumulator enabling 20 bits per sample period
- Sample to sample accumulator enabling up to 27 bits per data read
- 16-bit or 32-bit register or FIFO readout per channel
The ADPD144RI is a highly integrated, photometric front end optimized for photoplethysmography (PPG) detection of blood oxygenation (SpO2) by synchronous detection in red and infrared wavelengths. Synchronous measurement allows rejection of both dc and ac ambient light interference with extremely low power consumption.
The module combines highly efficient, light emitting diode (LED) emitters and a sensitive 4-channel, deep diffusion photodiode (PD1 to PD4) with a custom application specific integrated circuit (ASIC) in a compact package that provides optical isolation between the integrated LED emitters and the detection photodiodes to improve through tissue, signal-tonoise ratio (SNR).
The ASIC consists of a 4-channel analog front end (AFE) with two independently configurable datapaths with separate gain and filter settings, a 14-bit analog-to-digital converter (ADC) with a burst accumulator, two flexible, independently configurable, LED drivers, and a digital control block. The digital control block provides AFE and LED timing, signal processing, and communication. Data output and functional configuration occur over a 1.8 V I2C interface.
- Optical heart rate monitoring
- Reflective SpO2 measurement
Markets & Technology
Complete documentation is available upon completion of a Non-Disclosure Agreement (NDA) (pdf). Send your completed forms by e-mail to [email protected]. Additional support is available from your Analog Devices local sales.
Please contact the Optical Sensors Team for additional technical information.
For additional ADI Healthcare Products and related information, please visit www.gfeb.tw/healthcare.
Product Lifecycle Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
The EVAL-ADPD144RIZ-EB evaluation board provides users with a simple means of evaluating the ADPD144RI, a complete photometric system designed to measure optical signals from ambient light and from synchronous reflected light emitting diode (LED) pulses. The evaluation system includes the Applications WaveTool graphical user interface (GUI) that provides users with low level and high level configurability, real-time frequency and time domain analysis, and user datagram protocol (UDP) transfer capability so the evaluation board can easily interface to the user development system.
The EVAL-ADPD144RIZ-EB can interface with two different types of microcontroller boards, the EVAL-ADPDUCZ or the EVAL-ADPDM3Z microcontroller boards. Using the EVAL-ADPDUCZ requires a ribbon cable, this is obtained separately.
The design of the evaluation board is optimized for ear based photoplethysmography (PPG) measurements.
For additional information on the functionality of the ADPD144RI, refer to the ADPD144RI data sheet.
Features & Benefits
- Supports the detection of UART
- UDP transfer capability
- ADPD144RI full configuration
- Register level
- High level
- Graph view
- Time graph
- Frequency graph
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.