SNVAA70 june   2023 LM5176 , LM5176-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Principle of the TEC
    2. 1.2 Design Specification and Key Challenge
  5. 2Tec Driver Design Using Buck-Boost Controller
    1. 2.1 System Description
    2. 2.2 Block Diagram of TEC Design With LM5176
    3. 2.3 Output Voltage Control of LM5176
  6. 3Test Result
    1. 3.1 TEC Current Versus Output Voltage
    2. 3.2 Current Ripple Measurement Through TEC Element
    3. 3.3 Start-Up
    4. 3.4 Efficiency
  7. 4Summary
  8. 5References

3.3 Start-Up

Figure 3-11 and Figure 3-12 show the start-up of LM5176 at different output voltages. In this application note, the design starts up well under the voltage difference across the TEC element within 10 V. As the TEC element is connected between the Vin and Vout of the LM5176, the TEC element biases the Vout. Thus, TI recommends setting the initial Vout close to Vin for a more stable start-up and then regulate the Vout to required voltage.

CH1: SW1, CH2: SW2, CH3: VOUT, CH4: I TEC
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: I TECGUID-20230525-SS0I-SSTM-DNKQ-2MSFGB9D7PMD-low.pngFigure 3-11 15-V Input, 5-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: I TEC
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: I TECGUID-20230531-SS0I-TFQ5-1TCR-DKVXMWBBL7XP-low.pngFigure 3-12 15-V Input, 25-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: I TEC