SLVAFH3 December   2022 TPS6213013A-Q1 , TPS62130A-Q1 , TPS62133A-Q1 , TPS62150A-Q1 , TPS62152A-Q1 , TPS62153A-Q1 , TPS62901-Q1 , TPS62902-Q1 , TPS62903-Q1 , TPS62992-Q1 , TPS62993-Q1

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Achieving a Smaller Solution
    1. 2.1 Smaller Package and Fewer External Components
    2. 2.2 Smart Configuration Pin
    3. 2.3 VSET
  5. 3Reducing Power Loss
    1. 3.1 Junction Temperature
    2. 3.2 Automatic Efficiency Enhancement (AEE)
    3. 3.3 Quiescent Current
    4. 3.4 Auto PFM/PWM vs. Forced PWM
  6. 4Application Flexibility
    1. 4.1 1.0 MHz and 2.5 MHz Switching Frequencies
    2. 4.2 Lower and More Accurate Output Voltages
    3. 4.3 Output Voltage Discharge
    4. 4.4 Wettable Flanks
  7. 5Summary
  8. 6References

3.1 Junction Temperature

The TPS629xx-Q1 has an extended junction temperature of 165°C versus the 125°C of the TPS621x0A-Q1. This allows the device to operate at a higher output current while still maintaining a junction temperature within the recommended range. The main two factors that play a role in determining junction temperature are efficiency and thermal resistance. Using the TPS6290x-Q1 as an example, the efficiency under a 1 MHz switching frequency, 12-V input, 1.2-V output, and 3-A load current is 83%. After subtracting the inductor power loss, the IC power loss is 468 mW, and multiplying by the junction-to-ambient thermal resistance (RΘJA) gives a temperature rise of approximately 34°C. With this amount of temperature rise, the ambient temperature can be as high as 130°C while staying within the 165°C recommended operating junction temperature.

In comparison, the TPS621x0A-Q1 has a lower efficiency and lower operating junction temperature. For this device the ambient temperature must stay below 100°C for the junction temperature to remain under the 125°C recommended operating junction temperature.

Note: The efficiency depends on both input and output conditions, thus a recalculation of temperature rise would be needed to evaluate other operating points. In addition, the efficiency measurements were taken from the device's EVM using the XGL4020-222MEC inductor.