SBOA600 July   2024 ISOTMP35

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Calculating Thermal Response Time
    2. 1.2 Current Design with Non-Isolated Temperature Sensors
    3. 1.3 Proposed Design Using the ISOTMP35 Isolated Temperature Sensor
  5. 2Experiment Setup
    1. 2.1 Step 1: Prepare the Oil Bath
    2. 2.2 Step 2: Prepare the Liquid Gallium
    3. 2.3 Step 3: Submerge the Copper Pad
    4. 2.4 Step 4: Prepare Each PCB Configuration
    5. 2.5 Step 5: Testing Each PCB Configuration
    6. 2.6 Test Results
  6. 3Summary
  7. 4References

2.3 Step 3: Submerge the Copper Pad

The liquid gallium rises exactly to the edge of the copper pad, marked by the white arrows. The copper pad extends under the solder mask, up to the edge of the package (marked by the line inside the white arrows). The ISOTMP35 is thermally connected to the copper pad via being soldered to it. However, no part of the ISOTMP35 package can actually make direct contact with the liquid gallium. This is done to make sure all the thermal energy the ISOTMP receives comes from the thermal conductivity of the copper, not the liquid gallium pouring right onto the sensor.

PCB Layer View of Test PCB Figure 2-4 PCB Layer View of Test PCB
ISOTMP35 Mounted on Test PCBFigure 2-5 ISOTMP35 Mounted on Test PCB
Test PCB Placed in Liquid Gallium for Thermal Response TestFigure 2-6 Test PCB Placed in Liquid Gallium for Thermal Response Test