Power Supply Subsystem for MAX30001-Based ECG Remote Patient Vital Sign Monitor

要約

This application note is part of a series providing guidance for its readers to implement and validate a proven switch-mode power supply circuit for use in remote vital sign monitoring devices using Maxim Biosensing Analog Front Ends (AFEs). This document focuses on a vital sign monitor using the MAX30001 ECG AFE. Within this application note, readers will find reference schematics and layout (in popular EDA and PDF formats), validation check lists, and trouble-shooting guideline.

The figure below, shows a block diagram where the MAX30001 AFE device requires two power channels to power the digital supply, analog supply, and the OVDD (Logic Interface Voltage) supply.

This subsystem passes the performance limit criteria as specified by IEC60601 201.12.4.4.106 System Noise testing.

Design Limits

Input (VBATT) Output (VDIG, VANA) Noise, RTO
ViMIN ViMAX VoMIN VoMAX VPP(max)
3.0V1 4.2V1 1.6V 2.0V 30mVPP
1.0V2 3.4V2 1.6V 2.0V 30mVPP

1: Secondary cell battery (LiPo)

2: Primary cell batteries: a) Li Coin cell 2.0V-3.4V, b) Zinc Air cell 1.3V-1.7V, and c) Ag Oxide cell 1.2V-1.6V

Figure 1. MAX30001-Based ECG Remote Patient Vital Sign Monitor.

Figure 1. MAX30001-Based ECG Remote Patient Vital Sign Monitor.

Design Configuration Battery Implementation Board Area Layout Considerations
Discrete Primary (Coin and Button Cell)
Secondary (Li & LiPo)
  • Implements separate discrete circuits
Integrated Secondary (Li & LiPo)
  • Uses single integrated circuit for minimal board area requirements
  • Supports secondary batteries only

Discrete Power Supply Subsystems

Please use the following table and associated links to quickly access the discrete power supply subsystems of interest.

Battery TypesSMPS CircuitLink to Checklist
Output Voltage Input Power Input Power Input Power Input Power
1.8V 2.0-4.2V Batteries Li Ion (Primary Cell) LiPo (Secondary Cell) MAX38640A Discrete Design Description for 2.0V – 4.2V Batteries
1.8V 1.0-1.7V Batteries Zn Air (Primary Cell) Ag Oxide (Primary Cell) MAX17220 Discrete Design Description for 1.0V – 1.7V Batteries