Ultra-Low Power, Single-Channel Integrated Biopotential HR Detection AFE

Description

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The MAX30004 is a complete, biopotential, HR detection analog front-end solution for wearable applications, especially for chest straps and patches. It offers high performance for clinical and fitness applications, with ultra-low power for long battery life. The MAX30004 is a single biopotential channel providing R-R intervals for heart rate detection.

The biopotential channel has ESD protection, EMI filtering, internal lead biasing, DC leads-off detection, ultra-low power leads-on detection during standby mode, and extensive calibration voltages for built-in self-test. Soft power-up sequencing ensures no large transients are injected into the electrodes. The biopotential channel also has high input impedance, low noise, high CMRR, programmable gain, various low-pass and high-pass filter options, and a high-resolution analog-to-digital converter. The biopotential channel is DC coupled, can handle large electrode voltage offsets, and has a fast recovery mode to quickly recover from overdrive conditions, such as defibrillation and electrosurgery.

The MAX30004 is available in a 28-pin TQFN and 30-bump wafer-level package (WLP), operating over the 0°C to +70°C commercial temperature range.

Key Features

• Heart Rate Detection with Interrupt Feature Eliminates the Need to Extract and Process the ECG Data on the Microcontroller
  • Robust R-R Detection in High Motion Environment at Extremely Low Power
• Clinical-Grade Biopotential AFE with High-Resolution Data Converter
  • 15.5 Bits Effective Resolution with 5µV_P-P Noise
• Better Dry Starts Due to Much Improved Real World CMRR and High Input Impedance
  • Fully Differential Input Structure with CMRR > 100dB
• Offers Better Common-Mode to Differential Mode Conversion Due to High Input Impedance
  • High Input Impedance > 500MΩ for Extremely Low Common-to-Differential Mode Conversion
• Minimum Signal Attenuation at the Input During Dry Start Due to High Electrode Impedance
• High DC Offset Range of ±650mV (1.8V, typ) Allows to Be Used with Wide Variety of Electrodes
• High AC Dynamic Range of 65mV_P-P Will Help the AFE Not Saturate in the Presence of Motion/Direct Electrode Hits
• Longer Battery Life Compared to Competing Solutions
  • 85µW at 1.1V Supply Voltage
• Leads-On Interrupt Feature Keeps µC in Deep Sleep Mode with RTC Off Until Valid Lead Condition is Detected
  • Lead-On Detect Current: 0.7µA (typ)
• Configurable Interrupts Allows the µC Wake-Up Only on Every Heart Beat Reducing the Overall System Power
• High-Speed SPI Interface
• Shutdown Current of 0.5µA (typ)

Applications/Uses

• Chest Band Heart Rate Monitors for Fitness Applications
• Single Lead Wireless Patches for At-Home/In-Hospital Monitoring