company blog about ADI AD8233CB-EBZ Low Noise Heart Rate Monitor Evaluation Board For Wearable Product

ADI AD8233CB-EBZ Low Noise Heart Rate Monitor Evaluation Board For Wearable Product

Shenzhen Mingjiada Electronics Co., Ltd., a renowned distributor of electronic components, leverages its robust supply chain network to provide stable supply of ADI's AD8233CB-EBZ low-noise heart rate monitoring evaluation board. This offers wearable product developers comprehensive solutions spanning core evaluation to mass production.

【AD8233CB-EBZ Product Details】

The AD8233CB-EBZ evaluation board incorporates the AD8233 heart rate monitor (HRM) front-end and comes pre-configured with essential components for initial fitness application assessment. Input, output, power supply, and cable break detection pins are all connected to test pins, simplifying connection procedures. Input bias voltage, shutdown mode (SDN), right-leg drive shutdown (RLD SDN), fast recovery (FR), and AC/DC disconnection detection modes are configurable via switches and jumpers.

The AD8233CB-EBZ evaluation board is a four-layer board with components mounted solely on the primary side. The secondary side incorporates rubber feet for enhanced mechanical stability. A layout diagram is provided for visual reference and design guidance. The printed circuit board (PCB) adheres to standard specifications to ensure signal integrity and minimise manufacturing costs. Refer to AN-617 for optimal WLCSP layout practices.

【AD8233CB-EBZ Features】

- Ready-to-use HRM front end

- Supports dual-electrode or triple-electrode configurations

- Directly connectable to data acquisition systems and analogue-to-digital converters (ADCs)

- Switchable simplified mode selection

Supports multiple circuit configurations

Equipped with 3.5mm electrode interface

【Technical Advantages of the AD8233CB-EBZ Evaluation Board】

The AD8233CB-EBZ is a development board specifically designed for evaluating the AD8233 analogue front-end (AFE) chip. The AD8233 chip itself is a fully integrated single-lead analogue front end specifically designed for electrocardiogram (ECG) and heart rate monitoring applications, playing a crucial role in wearable device design.

The core value of this AD8233CB-EBZ evaluation board lies in enabling developers to rapidly validate and leverage the AD8233 chip's three key technical advantages:

Ultra-low power consumption and low noise: Operating at a typical current of just 50 microamperes (μA), coupled with exceptionally low input noise of 10 microvolts peak-to-peak (μV p-p), the AD8233 maximises device battery life while ensuring capture of faint, pure ECG signals. This makes it ideal for extended continuous monitoring.

Robust Motion Artifact Suppression: Wearables encounter significant signal interference during user movement. The AD8233's integrated bipolar high-pass filter effectively eliminates baseline drift and artifacts caused by motion or electrode contact. Its unique fast recovery capability swiftly stabilises after signal transients, ensuring real-time monitoring accuracy.

High Integration and Design Simplification: This chip highly integrates modules such as the instrumentation amplifier, filter, and right-leg drive (RLD) amplifier. Developers need not design complex analogue signal conditioning circuits from scratch. This significantly saves PCB space and material costs while accelerating product development cycles.

【Technical Decoding: How Does the AD8233CB-EBZ Overcome Noise Challenges?】

Capturing microvolt-level ECG signals from the wrist or other body parts is akin to discerning a whisper in a bustling marketplace. The core value of the AD8233CB-EBZ lies in its integrated AD8233 chip, which delivers a comprehensive noise countermeasure solution:

Built-in High-Performance Filters: The chip employs an innovative instrumentation amplifier architecture, tightly coupling two stages of high-pass filters with the amplifier. This effectively filters out low-frequency ‘motion artefacts’ and DC electrode potentials caused by movement or electrode contact. Simultaneously, a configurable operational amplifier allows users to build a third-order low-pass filter to eliminate high-frequency noise. The cutoff frequencies of all these filters can be flexibly configured via external resistors to suit diverse application requirements.

Superior common-mode rejection capability: The AD8233CB-EBZ evaluation board utilises the chip's integrated right-leg drive (RLD) amplifier to actively counteract common-mode noise such as mains interference, significantly enhancing signal acquisition immunity.

Rapid recovery functionality for assured responsiveness: This stands as a key highlight of the chip. Upon detecting sudden signal saturation—such as when an electrode detaches—the AD8233 automatically switches to a higher filter cutoff frequency, reducing stabilisation time from tens of seconds to mere seconds. This enables near-instant device readiness upon connection, markedly enhancing user experience.

Ultimate power consumption and size control: The AD8233 operates at a typical current of just 50μA and utilises an ultra-compact 2mm × 1.7mm WLCSP package. These characteristics are crucial for wearable devices prioritising extended battery life and miniaturisation.

【AD8233CB-EBZ Application】

The AD8233CB-EBZ serves as an evaluation platform designed for rapid prototyping, assisting engineers in integrating professional ECG functionality into end products.

Ecosystem Integration: Synergistic ECG+PPG

The most advanced wearable health monitoring solutions are evolving towards multimodal fusion of ECG and PPG (photoplethysmography). For instance, research has combined the AD8233 with PPG-enabled analogue front ends (such as the ADPD107) to build second-generation watch platforms. This convergence unlocks revolutionary application prospects:

Enhanced Heart Rate and Rhythm Analysis: ECG provides precise electrical signal reference, while PPG delivers continuous pulse information. Their integration enables mutual validation, improving heart rate monitoring accuracy and facilitating analysis of heart rate variability (HRV).

Non-invasive continuous blood pressure monitoring: By calculating the time difference between the arrival of the ECG R-wave and the PPG pulse wave at the fingertip (pulse transit time, PTT), blood pressure trends can be estimated non-invasively and continuously, representing a highly valuable health metric.

Stress and emotional state assessment: Integrating electrodermal activity (EDA), skin temperature, and heart rate data enables a more comprehensive evaluation of stress levels.

Mingjiada Electronics maintains long-term supply of other ADI evaluation board components, including but not limited to the following models:

AD8556CP-EBZ

EVAL-ADA4352-2EBZ

ADL5309-EVALZ

ADL5309-KIT-EVALZ

ADL5308-EVALZ

EVAL-AD8460SDZ

EVAL-ADA4511-2ARZ

EVAL-ADA4351-2EBZ

ADL6337-EVALZB

AD8410ARM-EVALZ

AD8411AR-EVALZ

AD8411ARM-EVALZ

EVAL-ADA4097-2EBZ

EVAL-ADA4098-2EBZ