TIDUFE6A September   2025  – December 2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Control Pilot
        1. 2.2.1.1 Signals
        2. 2.2.1.2 Duty Cycle
        3. 2.2.1.3 Signal State
        4. 2.2.1.4 Control Pilot Signal Circuit
        5. 2.2.1.5 EV Simulation Circuit
      2. 2.2.2 HomePlug Green PHY - Powerline Communication
        1. 2.2.2.1 HomePlug Green PHY Circuit
      3. 2.2.3 Proximity Pilot
        1. 2.2.3.1 Type 1 and NACS
        2. 2.2.3.2 Type 2
        3. 2.2.3.3 Proximity Detection Circuit
      4. 2.2.4 GB/T – ChaoJi
        1. 2.2.4.1 Signals
        2. 2.2.4.2 GB/T
        3. 2.2.4.3 ChaoJi
        4. 2.2.4.4 Schematics
        5. 2.2.4.5 EV Simulation
      5. 2.2.5 CHAdeMO
        1. 2.2.5.1 Signals
        2. 2.2.5.2 Standard
        3. 2.2.5.3 Schematics
          1. 2.2.5.3.1 High-Side Switch (CS1)
          2. 2.2.5.3.2 Low-Side Switch (CS2)
          3. 2.2.5.3.3 Proximity Detection
          4. 2.2.5.3.4 Vehicle Charge Permission
        4. 2.2.5.4 EV Simulation
      6. 2.2.6 Pluck Lock
        1. 2.2.6.1 Signals
        2. 2.2.6.2 Schematics
        3. 2.2.6.3 Motor Driver
        4. 2.2.6.4 Solenoid Driver
      7. 2.2.7 Temperature Sensing
        1. 2.2.7.1 Signals
        2. 2.2.7.2 Schematics
        3. 2.2.7.3 Calculation
      8. 2.2.8 Connectivity
        1. 2.2.8.1 RS-485
        2. 2.2.8.2 RS-232
        3. 2.2.8.3 CAN
      9. 2.2.9 General Purpose Input/Output
        1. 2.2.9.1 Digital Input
        2. 2.2.9.2 Analog Input
        3. 2.2.9.3 Digital Output
    3. 2.3 Highlighted Products
      1. 2.3.1 MSPM0G3507
      2. 2.3.2 AM62L
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
    2. 3.2 Test Setup
      1. 3.2.1 Power Supply Options
      2. 3.2.2 XDS110 Debug Probe
        1. 3.2.2.1 Application (or Back Channel) UART
        2. 3.2.2.2 Using an External Debug Probe Instead of the Onboard XDS110
      3. 3.2.3 Connecting to the AM62L-EVM
      4. 3.2.4 Connector, Pin Header, and Jumper Settings
    3. 3.3 Test Results
      1. 3.3.1 Control Pilot
        1. 3.3.1.1 TLV1805 Output Rise and Fall Time
        2. 3.3.1.2 Control Pilot Signal Voltage Accuracy in Different States
      2. 3.3.2 GB/T ChaoJi
        1. 3.3.2.1 GB/T Signal Voltage Accuracy
        2. 3.3.2.2 ChaoJi Signal Voltage Accuracy in Different States
      3. 3.3.3 Digital and Analog Input
        1. 3.3.3.1 Digital In
        2. 3.3.3.2 Analog In
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author
  12. 6Revision History

2.2.7.2 Schematics

This temperature sensing circuit uses a resistor in series with a positive–temperature–coefficient (PTC) thermistor to form a voltage–divider, which has the effect of producing an output voltage that is linear over temperature. The series resistor limits the measurement current to prevent self-heating of the PTC sensor. For PT1000 thermistors, a typical measuring current between 0.1mA to 1mA is recommended, depending on the manufacturer.

TIDA-010939 Temperature Sensing Circuit Figure 2-21 Temperature Sensing Circuit

The output of the voltage divider is directly connected to the ADC input of the MSPM0 microcontroller without additional amplification or buffering. To still provide precise measurements despite the higher source impedance, a longer ADC sampling time can be configured in software. The sample-and-hold time determines how long the signal is sampled before digital conversion. During this time, the internal switch of the ADC connects the signal to the sample-and-hold capacitor, allowing the capacitor to be charged. A longer sampling time makes sure that this capacitance reaches the correct voltage level, even when driven by higher-impedance sources.

Since temperature signals change slowly and predictably, fast sampling is not necessary in this application. Additionally, the hardware of the MSPM0 averaging feature can be used to further increase the effective resolution of the ADC, reducing noise and improving accuracy without the need for software and CPU intervention.