TIDUC65 April   2022 TPSI3050 , TPSI3050-Q1 , TPSI3052 , TPSI3052-Q1

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products
    3. 2.3 Design Considerations
      1. 2.3.1 Overcurrent Protection (OCP)
        1. 2.3.1.1 Immediate Overcurrent Protection
        2. 2.3.1.2 Adjustable Delay Overcurrent Protection
      2. 2.3.2 Overtemperature Protection (OTP)
        1. 2.3.2.1 TMP392
        2. 2.3.2.2 ISO7310
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Test Setup
    3. 3.3 Test Results
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
      3. 4.1.3 Altium Project
      4. 4.1.4 Assembly Drawings
      5. 4.1.5 Gerber Files
    2. 4.2 Documentation Support
    3. 4.3 Support Resources
    4. 4.4 Trademarks
  10. 5About the Author

2.3.2.1 TMP392

The TMP392 device is part of a family of ultra-low power, dual channel, resistor programmable temperature switches that enable protection and detection of system thermal events from 30 °C to 130 °C. The TMP392 offers dual overtemperature (hot and warm) detection. The trip temperatures (TTRIP) and thermal hysteresis (THYST) options are programmed by two E96-series resistors (1 % tolerance) on the SETA and SETB pins. Channel A resistors can range from 1.05 kΩ to 909 kΩ, representing one of 48 unique values. Channel B resistors can range from 10.5 kΩ to 909 kΩ.

The value of the resistor to ground on SETA input sets the TTRIP threshold of Channel A. The value of the resistor to ground on SETB input sets the TTRIP threshold of Channel B, as well as the THYST options of 5 °C, or 1 °C for both channels, to prevent undesired digital output switching. When the SETB input is connected to ground, Channel A operates with 20 °C hysteresis.

TMP392 Features:

  • Resistor programmable temperature trip points
  • Dual output selection
  • Ultra-low power consumption
  • Open-drain outputs
GUID-20220406-SS0I-KL35-Z1ND-5M9B9T3CDXXJ-low.gif Figure 2-5 Overtemperature Detection Circuit

For this design, the dual overtemperature protection was selected such that when temperature is between 60 °C to 90 °C, a visual warning is provided via a red LED. The LED selected for this design is LSL29K-G1H2-1-Z which only requires 2 mA to provide high luminous intensity. TPSI3050-Q1 can provide a max of 50 mW of power that must be carefully distributed for the auxiliary circuitry. When the temperature is higher than 90 °C the circuit immediately disconnects the load. The Channel A (HOT) temperature is set to trip at 90 °C by the 78.7 kΩ resistor between SETA and ground while Channel B (WARM) is set to trip at 60 °C by the 38.3 kΩ resistor connected between SETB and ground. The 38.3 kΩ resistor on SETB also set the hysteresis for both channels to 5 °C.