JAJU873 August   2020

 

  1.   概要
  2.   リソース
  3.   特長
  4.   アプリケーション
  5.   5
  6. 1 System Description
    1. 1.1 Medical Respiratory Systems
    2. 1.2 Respirator System Components
    3. 1.3 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Brushless DC Motor (BLDC)
        1. 2.2.1.1 DRV8323RS BLDC Motor Driver Design Calculations
        2. 2.2.1.2 BLDC Motor Driver Circuit
      2. 2.2.2 Solenoid Valve Drivers
        1. 2.2.2.1 DRV8847 Solenoid Driver Design Calculations
        2. 2.2.2.2 Solenoid Driver Circuit
      3. 2.2.3 Power Tree Architecture
        1. 2.2.3.1 Input protection - overvoltage and reverse voltage
        2. 2.2.3.2 LM5122 Boost Design Calculations
        3. 2.2.3.3 LMR33630 Buck Design Calculations
        4. 2.2.3.4 Secondary Power Stage – TPS62840 3.3V Buck
        5. 2.2.3.5 Secondary Power Stage – TPS7A02 3.3V LDO
        6. 2.2.3.6 Power Tree Circuit
    3. 2.3 Highlighted Products
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware and Software Requirements
    2. 3.2 Test Setup
      1. 3.2.1 Hardware Configuration
      2. 3.2.2 Software Configuration
    3. 3.3 Test Results
      1. 3.3.1 Motor Test Result
      2. 3.3.2 Valve Test Result
      3. 3.3.3 Power Tree Test Result
      4. 3.3.4 Key Test Summary
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Documentation Support
    3. 4.3 サポート・リソース
    4. 4.4 Trademarks
  10. 5About the Author

3.3.2 Valve Test Result

The following valve tests were conducted:

  • Valve Turn-On Time (Makeblock 59001)
  • Valve Turn-Off Time (Makeblock 59001)
  • Consecutive Valve operation (2x Makeblock 59001)
  • Bidirectional Valve operation (Spartan Scientific 3827-B60-AA82B)

DRV8847 Valve Turn-On Time

The valve turn-on transition (<400 ns) is clean with minimal overshoot as shown in channel 1 in Figure 3-19.

GUID-20200801-CA0I-PK06-KRKV-PGWMMWJVLNRC-low.png Figure 3-19 DRV8847 Valve Turn-On Time

DRV8847 Valve Turn-Off Time

The valve turn-off transition (<400ns) is clean with minimal overshoot as shown in channel 1 in Figure 3-20.

GUID-20200801-CA0I-QXW6-VTTC-CD2GBTGN9L5T-low.png Figure 3-20 DRV8847 Valve Turn-Off Time

DRV8847 Consecutive Valve Operation

The transition between valves is clean with no overshoot as shown in channel 1 and 2 in Figure 3-21. Valve is seen and heard to engage during both events.

GUID-20200801-CA0I-ZJW8-SFXT-VQFPGJT3L71K-low.png Figure 3-21 DRV8847 Consecutive Valve Operation

DRV8847 Bidirectional Valve Operation

The voltage waveforms for each side matched as shown in channel 1 and 2 in Figure 3-22. The observed current draw was the same for either direction. The valve is seen and heard to engage during both events.

GUID-20200801-CA0I-FGT9-359B-KZG7GTSSGK1T-low.png Figure 3-22 DRV8847 Bidirectional Valve Operation