TIDUDO6B May   2019  – October 2020

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Introduction to Parameters Measured Using TIDA-01580
    2. 1.2 High-Level System Description
    3. 1.3 Typical Applications
    4. 1.4 System Specifications and Design Features
    5. 1.5 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products
      1. 2.2.1 AFE4900
      2. 2.2.2 CC2640R2F
      3. 2.2.3 TPS61099
      4. 2.2.4 TPS63036
      5. 2.2.5 TPD1E10B06
    3. 2.3 System Design Theory and Design Considerations
      1. 2.3.1  AFE4900 and Power Supply
      2. 2.3.2  CC2640R2F Microcontroller
      3. 2.3.3  PPG Measurement
      4. 2.3.4  ECG Measurement
        1. 2.3.4.1 Two-Electrode Configuration
        2. 2.3.4.2 Three-Electrode Configuration
      5. 2.3.5  Selecting TX Supply (TX_SUP) Value for Driving LEDs
      6. 2.3.6  Generating TX Supply for Driving LEDs
        1. 2.3.6.1 Programming Output Voltage
        2. 2.3.6.2 Maximum Output Current
        3. 2.3.6.3 Input and Output Capacitor Selection
        4. 2.3.6.4 Switching Frequency
        5. 2.3.6.5 WEBENCH® Simulation for TPS61099 Boost Converter
      7. 2.3.7  Generating RX Supply for AFE4900
        1. 2.3.7.1 Setting Output Voltage
        2. 2.3.7.2 Capacitor Selection
        3. 2.3.7.3 Output Current Limit
        4. 2.3.7.4 Inductor Selection
        5. 2.3.7.5 TINA-TI™ Simulation for TPS63036
      8. 2.3.8  Generating I/O Supply
      9. 2.3.9  Battery Input and Reservoir Capacitors
      10. 2.3.10 Battery Life Calculations
        1. 2.3.10.1 AFE4900 Current Consumption
        2. 2.3.10.2 CC2640R2F Current Consumption
        3. 2.3.10.3 On-State Current Calculations
        4. 2.3.10.4 Off-State Current Calculations (Considering Battery Voltage = 3 V)
      11. 2.3.11 External Memory
      12. 2.3.12 LED Indications
      13. 2.3.13 Connections Between Sensor Board and ECG Board
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
      1. 3.1.1 Hardware
        1. 3.1.1.1 Connecting Optical Sensor and ECG Boards to Main Board
        2. 3.1.1.2 Difference Between PPG Sensor Boards
      2. 3.1.2 Software
        1. 3.1.2.1 Software Loading for TIDA-01580 Board (Transmit Side of BLE)
        2. 3.1.2.2 LabVIEW™ File Execution for Checking Measurement Data (Receive Side of BLE)
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
      2. 3.2.2 Test Results
        1. 3.2.2.1 Heart-Rate Measurement Using PPG (Green LED) and ECG
        2. 3.2.2.2 SpO2 Measurement Using Red and IR LEDs
        3. 3.2.2.3 PTT Measurement
        4. 3.2.2.4 Lead-Off Detect
          1. 3.2.2.4.1 AC Lead-Off Detect
          2. 3.2.2.4.2 DC Lead-Off Detect
        5. 3.2.2.5 Low-Battery Indication
        6. 3.2.2.6 Waveforms for DC/DC Converters
        7. 3.2.2.7 Battery Life Test
  9. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 PCB Layout Recommendations
      1. 4.3.1  Layout for Main Board
      2. 4.3.2  Connection From PDs to AFE
      3. 4.3.3  Connections From LEDs to AFE
      4. 4.3.4  Connections From ECG PADs to AFE
      5. 4.3.5  Connections Between BT and AFE
      6. 4.3.6  Connections Between BT Antenna and Chip
      7. 4.3.7  Boost Converter
      8. 4.3.8  Buck-Boost Converter
      9. 4.3.9  Layouts for PPG Sensor Boards
      10. 4.3.10 Layout for ECG Sensor Board
      11. 4.3.11 Layout Prints
    4. 4.4 Altium Project
    5. 4.5 Gerber Files
    6. 4.6 Assembly Drawings
  10. 5Software Files
  11. 6Related Documentation
    1. 6.1 Trademarks
  12. 7About the Authors
  13.   Revision History

2.3.10.4 Off-State Current Calculations (Considering Battery Voltage = 3 V)

The RX_SUP current at low-power operation (15 µA at software power-down mode and 1 µA at hardware power-down mode) = 16 µA (worst case). The TX_SUP current at low-power operation (1 µA at software power-down mode, 1 µA at hardware power-down mode) = 2 µA (worst case). The net total current supplied to the CC2640R2F device is taken as 200 nA (shutdown), 5 µA (standby), and 550 µA (idle).

Now, reflected current on the input side of TPS61099 is

Equation 16. GUID-20200928-CA0I-PVZ4-PPMN-PZKDS60WX4FN-low.gif
Equation 17. GUID-20201001-CA0I-LFGX-NR7Q-TKJJLL7ZVDXS-low.gif
Equation 18. GUID-20201001-CA0I-BXQB-KJMN-TDTS4DNQVTB3-low.gif
Equation 19. GUID-20201001-CA0I-PQRK-NFN4-VBZLGTHVTVXM-low.gif
Equation 20. GUID-20201001-CA0I-KRLC-M2CQ-VVGFNMKGCSLG-low.gif

Table 2-11 lists the battery lifetime for the cases shown.

Table 2-11 Battery Life Calculations
MODEON-STATE CURRENT (mA)OFF-STATE CURRENT (µA)BATTERY LIFE FOR 20s/MIN DUTY CYCLE (DAYS)BATTERY LIFE FOR 5 s/MIN DUTY CYCLE (DAYS)BATTERY LIFE FOR 1 s/MIN DUTY CYCLE (DAYS)
Shutdown4.0966.0414.852156
Standby4.0970.8414.751151
Idle4.09665.8411.52229

With TI’s newer ultra-low noise Iq device (TPS63900), the off current of the system will change significantly. Table 2-12 shows the updated numbers with this new buck-boost converter.

Equation 21. GUID-20200928-CA0I-PVZ4-PPMN-PZKDS60WX4FN-low.gif
Equation 22. GUID-20200928-CA0I-BC6V-MKLT-KCRPTPQZKBN4-low.gif
Equation 23. GUID-20200928-CA0I-DXFH-HZBG-RRLD8GXHPFFL-low.gif
Equation 24. GUID-20200928-CA0I-1C29-H03D-N4JVXC7781QR-low.gif
Equation 25. GUID-20200928-CA0I-Q6JP-KNM1-HSC6VG2JG53W-low.gif
Table 2-12 Battery Life Calculations (TPS63900)
MODE ON-STATE CURRENT (mA) OFF-STATE CURRENT (µA) BATTERY LIFE FOR 20s/MIN DUTY CYCLE (DAYS) BATTERY LIFE FOR 5 s/MIN DUTY CYCLE (DAYS) BATTERY LIFE FOR 1 s/MIN DUTY CYCLE (DAYS)
Shutdown 4.09 26.56 15 57 221
Standby 4.09 31.36 15 56 210
Idle 4.09 626.36 11.7 23 30