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

3.2 Current Ripple Measurement Through TEC Element

The maximum temperature differential across the element decreases if the ripple current increases. Thus, the maximum ripple current is recommended to be less than 10% for peak performance. Figure 3-7, Figure 3-8, Figure 3-9, and Figure 3-10 show the ripple current under different output voltages. All the tests meet the ripple requirement.

CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRipple
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRippleGUID-20230525-SS0I-T7PT-LWKD-6F47CCMVZNQS-low.pngFigure 3-7 15-V Input, 5-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRipple
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRippleGUID-20230525-SS0I-JGPB-P4VB-10PBZX26TCDR-low.pngFigure 3-9 15-V Input, 17-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRipple
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRippleGUID-20230525-SS0I-G2PV-6RJJ-T1DRN4CVGJ06-low.pngFigure 3-8 15-V Input, 13-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRipple
CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRippleGUID-20230525-SS0I-7VBL-6SLT-41C2DJQZM9JJ-low.pngFigure 3-10 15-V Input, 25-V Output. CH1: SW1, CH2: SW2, CH3: VOUT, CH4: IRipple