on November 7th 63

MAX30003 Biopotential AFE Guide: Circuit Analysis, Pin Configuration, Datasheet, and AD8232 Comparison

Wearable technology has reshaped how we approach health monitoring, seamlessly merging convenience with clinical-grade functionality. Dominant to this evolution is the MAX30003, a sophisticated biopotential analog frontend tailored for wearables and remote health monitoring devices. It is designed for energy efficiency and precision and enables accurate electrocardiogram (ECG) readings and health insights, making it a popular choice. In this article, we dig into the MAX30003’s advanced features, from its low power consumption and noise-filtering capabilities to its flexible design that supports diverse health-monitoring applications, exploring how it contributes to reliable, continuous patient care and fitness tracking.

Catalog

Overview of MAX30003

The MAX30003 is a versatile biopotential analog front-end, ideal for wearable technology that targets both clinical and fitness applications. Designed for power efficiency, it supports prolonged battery life while delivering reliable heart rate and ECG monitoring. With a single biopotential channel, the MAX30003 efficiently measures ECG and heart rate, making it suitable for a wide range of health monitoring needs. This low-power feature extends to an ultra-low-power standby mode, making it ideal for devices requiring continuous monitoring over long durations without frequent recharging.

The device incorporates electrostatic discharge (ESD) protection and electromagnetic interference (EMI) filtering to enhance reliability across varied conditions. These safeguards are useful for devices frequently exposed to electrical disruptions, which can otherwise compromise data integrity. By addressing these issues, the MAX30003 ensures accurate data and device resilience, basic for reliable monitoring in both clinical and fitness environments. This robust protection supports consistent performance, meeting the demands for long-lasting, dependable wearable devices.

Additional features, such as internal lead biasing and automatic lead-off detection, further improve the MAX30003’s usability. With high input impedance, low noise, and customizable gain settings, the device is adaptable to different signal intensities, ensuring precision across applications. Its integrated low-pass and high-pass filters enhance signal clarity, while the high-resolution ADC plays a dangerous role in gathering accurate measurements, dynamic for detailed health data analysis.

Pin Configuration

Pin Number	Pin Name	Description
1, 2, 4, 5, 24, 26	I.C.	Internally Connected. Connect to AGND.
3, 8, 28	AGND	Analog Power and Reference Ground. Connect into the printed circuit board ground plane.
6	ECGP	ECG Positive Input
7	ECGN	ECG Negative Input
9	CAPP	Analog High-Pass Filter Input. Connect a 1μF X7R capacitor (CHPF) between CAPP and CAPN to form a 0.5Hz high-pass response in the ECG channel.
10	CAPN	Analog High-Pass Filter Input. Connect a 1μF X7R capacitor (CHPF) between CAPP and CAPN to form a 0.5Hz high-pass response in the ECG channel.
11	CPLL	PLL Loop Filter Input. Connect 1nF COG cap between CPLL and AGND.
12	DGND	Digital Ground for Both Digital Core and I/O Pad Drivers. Recommended to connect to AGND plane.
13	DVDD	Digital Core Supply Voltage. Connect to AVDD.
14	FCLK	External 32.768kHz Clock that Controls the Sampling of the Internal Sigma-Delta Converters and Decimator.
15	CSB	Active-Low Chip-Select Input. Enables the serial interface.
16	SCLK	Serial Clock Input. Clocks data in and out of the serial interface when CSB is low.
17	SDI	Serial Data Input. SDI is sampled into the device on the rising edge of SCLK when CSB is low.
18	SDO	Serial Data Output. SDO will change state on the falling edge of SCLK when CSB is low. SDO is three-stated when CSB is high.
19	OVDD	Logic Interface Supply Voltage
20	INT2B	Interrupt 2 Output. INT2B is an active-low status output. It can be used to interrupt an external device.
21	INTB	Interrupt Output. INTB is an active low status output. It can be used to interrupt an external device.
22	AVDD	Analog Core Supply Voltage. Connect to DVDD.
23	VREF	ADC Reference Buffer Output. Connect a 10μF X5R ceramic capacitor between VREF and AGND.
25	VCM	Common Mode Buffer Output. Connect a 10μF X5R ceramic capacitor between VCM and AGND.
27	VBG	Bandgap Noise Filter Output. Connect a 1.0μF X7R ceramic capacitor between VBG and AGND.
EP	—	Exposed Paddle. Connect to AGND.

CAD Models

Symbols

Footprints

3D Models

Features

Feature	Description
Clinical-Grade ECG AFE	High-resolution data converter with 15.5 bits effective resolution and 5 µV P-P noise
Improved Real-World CMRR	Enhanced dry start capability with fully differential input structure and CMRR > 100dB
High Input Impedance	High impedance > 500 MΩ for low common-to-differential mode conversion
Minimum Signal Attenuation	Reduces signal loss at input during dry starts due to high electrode impedance
High DC Offset Range	±650 mV (typical at 1.8V), compatible with various electrodes
High AC Dynamic Range	65 mV P-P, prevents AFE saturation from motion or direct electrode hits
Longer Battery Life	Consumes only 85 µW at 1.1V supply voltage
Leads-On Interrupt Feature	Allows microcontroller to remain in deep sleep mode until valid lead condition is detected
Lead-On Detect Current	Low current of 0.7 µA (typical)
Built-In Heart Rate Detection	Onboard HR detection with interrupt feature, reducing microcontroller processing load
Robust R-R Detection	Effective in high-motion environments with very low power consumption
Configurable Interrupts	Allows microcontroller wake-up on every heartbeat, reducing system power
High Accuracy	Enables extraction of more physiological data
32-Word FIFO Buffer	Supports waking up microcontroller every 256 ms with full ECG acquisition
High-Speed SPI Interface	Facilitates quick data transfer
Low Shutdown Current	Consumes only 0.5 µA (typical) in shutdown mode

Technical Specification

Here’s the technical specification table for the Maxim Integrated MAX30003CTI+.

Type	Parameter
Factory Lead Time	9 Weeks
Mounting Type	Surface Mount
Package / Case	28-WFQFN Exposed Pad
Surface Mount	YES
Number of Pins	28
Packaging	Tray
Published	2016
JESD-609 Code	e3
Pbfree Code	Yes
Part Status	Active
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Number of Terminations	28
Type	ECG Front End
Terminal Finish	Matte Tin (Sn)
Max Operating Temperature	70°C
Min Operating Temperature	0°C
Applications	Heart Rate Monitoring
HTS Code	8542.39.00.01
Terminal Position	QUAD
Terminal Form	NO LEAD
Peak Reflow Temperature (Cel)	260
Number of Functions	1
Supply Voltage	1.8V
Terminal Pitch	0.5mm
Time@Peak Reflow Temperature-Max (s)	NOT SPECIFIED
Base Part Number	MAX30003
Temperature Grade	COMMERCIAL
Max Supply Voltage	2V
Min Supply Voltage	1.2V
Length	5mm
Height Seated (Max)	0.8mm
Width	5mm
REACH SVHC	No SVHC
RoHS Status	ROHS3 Compliant

Parts for Comparison

Part Number	Manufacturer	Package / Case	Number of Pins	Min Supply Voltage	Supply Voltage	Max Supply Voltage	RoHS Status	Mounting Type	Peak Reflow Temperature
MAX30003CTI+	Maxim Integrated	28-WFQFN Exposed Pad	28	1.2 V	1.8 V	2 V	ROHS3 Compliant	Surface Mount	260
TLV320AIC23BIPWR	Texas Instruments	28-WFQFN Exposed Pad	28	1.5 V	3.3 V	3.6 V	ROHS3 Compliant	Surface Mount	260
TLV320AIC23BIRHD	Texas Instruments	28-TSSOP (0.173, 4.4mm)	28	1.42 V	-	3.6 V	ROHS3 Compliant	Surface Mount	260
SSM2603CPZ-REEL7	Analog Devices Inc.	28-VFQFN Exposed Pad	28	1.42 V	-	3.6 V	ROHS3 Compliant	Surface Mount	260
TLV320AIC23BRHDR	Texas Instruments	28-VFQFN Exposed Pad	28	1.42 V	-	3.6 V	ROHS3 Compliant	Surface Mount	260

Functional Block Diagram

MAX30003 Circuit Integration

In ECG systems, electrodes affixed to the skin detect potential differences originating from the heart's subtle electrical activity. The MAX30003 exploits a dedicated biopotential channel to capture these signals. Through the strategic integration of numerous MAX30003 units in parallel, multi-lead configurations, such as those in a 3-lead Holter monitor, can be crafted. Typically, this arrangement necessitates the use of two units, leveraging signal processing to derive the third lead.

3-Lead Holter Monitor with MAX30003

The MAX30003 is adept at supporting the architecture of a 3-lead Holter monitor. A Wilson Central Terminal (WCT) is a key component in this design, averaging potentials from three strategically placed electrodes, and aiding in noise minimization. The device is engineered to adeptly manage interference from common sources, like electrical lines, ensuring the extraction of a pristine signal devoid of noise.

In applications, a thoughtfully architected 3-lead system with precise electrode placement can substantially elevate the diagnostic process by offering a broader view of cardiac dynamics. Research indicates that a sturdy 3-lead configuration provides dependable continuous monitoring. Such a system is advantageous for the timely detection of arrhythmias.

Noise and Common-Mode Interference

ECG signal quality is frequently challenged by external noise, stemming from line interference, motion-related artifacts, and muscle contractions. The MAX30003 integrates cutting-edge filtering methodologies to counteract these disturbances. Its high Common-Mode Rejection Ratio (CMRR) and advanced differential input circuitry significantly curb common-mode noise, thereby elevating signal integrity. Utilizing an extra electrode for active noise cancellation further purifies the captured signal.

Experiences highlight that sustaining consistent signal quality benefits greatly from strategic electrode placement and adherence to recommended practices, such as ensuring a firm contact between electrodes and skin and advising relative stillness during ECG recordings. These measures are effective in reducing distortions and artifacts.

Body Potential Management

In portable ECG configurations, effective management of body potential is required to achieve precise readings. The MAX30003 adopts a dedicated right leg (RL) electrode to stabilize body potential, preventing electrical drift and ensuring amplifiers operate within their optimal range. In configurations lacking an RL electrode, the management of body potential can be facilitated through the use of programmable lead bias resistors.

The effective management of body potential can markedly affect measurement accuracy. Incorporating feedback loops and embedding adaptive algorithms to dynamically manage body potential is a viable approach to obtaining more accurate and consistent readings, especially in diverse physiological and environmental settings.

Typical Application Schematic

Use Case Circuit

Comparing MAX30003 and AD8232 Specifications

Attribute	MAX30003	AD8232
Base Product Number	MAX30003	AD8232
Category	Integrated Circuits (ICs) Specialized ICs	Development Boards, Kits, Programmers Evaluation and Demonstration Boards and Kits
Manufacturer	Maxim Integrated	Analog Devices Inc.
Series	-	-
Package	Tray	Box
Part Status	Active	Active
Type	ECG Front End	Interface

Popular Uses for the MAX30003 ECG Sensor

The MAX30003 is mainly well-suited for various applications, notably in health monitoring, fitness tracking, and bio-authentication. Exploring these domains highlights their tangible impact and advantages in everyday use.

Single-Lead Event Monitors for Observing Arrhythmia

In the world of arrhythmia observation, devices featuring the MAX30003 chip stand out for their ability to detect and monitor irregular heart rhythms. With the capability to identify anomalies early and precisely, these monitors are a dynamic tool for timely medical response. A range of modern healthcare devices incorporates event monitors for continuous heart rhythm tracking. They employ sophisticated algorithms to discern minor irregularities from more severe conditions, thereby bolstering patient care.

Wireless Patches for Remote Monitoring of Patients

The advent of wireless patches incorporating the MAX30003 is transforming remote patient surveillance. These devices enable uninterrupted ECG data sharing, empowering you to oversee cardiac health remotely. The technology proves advantageous for you, offering the comfort of reduced hospital visits. The reliability and precision these patches provide ensure that healthcare decisions are made promptly and with insight.

Fitness Trackers Heart Rate Monitors in Chest Bands

In fitness circles, chest bands with heart rate monitors that include the MAX30003 are extensively utilized. These instruments deliver accurate heart rate metrics, aiding athletes and fitness devotees in refining their training strategies. By interpreting biometric data, individuals can adapt their exercises to achieve targeted heart rate zones, thereby boosting the effectiveness and safety of their workouts. The utility and success of these monitors are well-established across different fitness environments.

ECG-Based Verification in Bio-Authentication Systems

Bio-authentication systems leveraging ECG-based verification offer a cutting-edge application of the MAX30003. By harnessing the distinctive electrical signals of a person's heart, these systems provide a robust and trustworthy form of identity verification. This method is gaining traction in high-security areas where conventional systems may fail. The individualized nature of ECG patterns ensures a formidable barrier against unauthorized access, reinforcing security protocols dramatically.

Manufacturer Overview

Maxim Integrated, now part of Analog Devices, holds a substantial role as a leading provider of analog and mixed-signal ICs. This integration positions the company to harness extensive industry knowledge, enabling the development of sophisticated and pioneering solutions. Rooted in a profound understanding of technological evolution and your needs, their innovations are guided by a blend of expertise and market intuition.

Within the automotive sphere, Maxim creates solutions that elevate vehicle dynamics, bolster safety measures, and enhance driver interactions. Their power management ICs are key in optimizing energy use, ensuring reliability even amidst challenging environments. By aligning advanced engineering with an exact understanding of automotive demands, Maxim actively contributes to the future of driving technology.

Datasheet PDF

TLV320AIC23BIPWR Datasheets:

TLV320AIC23B.pdf

TLV320AIC23BIRHD Datasheets:

TLV320AIC23B.pdf

SSM2603CPZ-REEL7 Datasheets:

SSM2603.pdf

TLV320AIC23BRHDR Datasheets:

TLV320AIC23B.pdf