SDAA210 November   2025 LM5125-Q1 , LM51251A-Q1 , LM5125A-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Application Implementation
  6. 3Design Considerations
  7. 4Test Results
    1. 4.1 Efficiency Measurements
    2. 4.2 Device Features
      1. 4.2.1 Soft-Start (SS)
      2. 4.2.2 Over-Voltage Protection (OVP)
      3. 4.2.3 Second phase enable (EN2)
      4. 4.2.4 Bypass mode
    3. 4.3 Load Transient
    4. 4.4 Line Transient
    5. 4.5 Temperature Measurements
    6. 4.6 Bode Plot
  8. 5Summary
  9. 6References

4.2.3 Second phase enable (EN2)

A square wave with 100Hz frequency was applied to the EN2 pin, to repeatedly turn on and off the second phase and see how the device behaves. As shown in Figure 4-4, the inductor currents (in orange and blue, respectively) flow according to the EN2 signal (in green). The output voltage (in yellow) shows over/undershoot of acceptable magnitude (hundreds of millivolt) with a fast recovery. The load current used for this test is 3A.

Turning on and Off of Phase 2 Figure 4-4 Turning on and Off of Phase 2