SLVAG06 March   2025 TPS40210 , TPS40210-Q1 , TPS40211 , TPS40211-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Primary Side Regulation (PSR)
  6. 3Secondary Side Regulation Implementation
    1. 3.1 Common Implementation Feedback for Secondary Side Regulation
    2. 3.2 Implementing Feedback for Secondary Side Regulation
  7. 4Simulation Results
  8. 5Practical Bode Plot Comparison
  9. 6Summary
  10. 7References

3.1 Common Implementation Feedback for Secondary Side Regulation

The TPS40210 device integrates the error amplifier and reference. In non-isolated flyback or boost topology, these features are used. On the secondary side regulation, owing to TL431 on the secondary or discrete amplifier with reference voltage. The TL431 device acts as an error amplifier with reference voltage. The TPS40210 device doesn't require an internal amplifier. FB can connect to ground. Equation 1 shows the comp to output transfer function.

Equation 1. VcompVout=RpullupRled*CTR*[1+SComp*(Rfb1+Rcomp]S*Rfb1*Comp*1+SComp*Rpullup1+S*Copto*Rpullup

Copto is the optocoupler parasitic capacitance (commonly 1nF to 5nF)

Feedback Implementation of Secondary Side Regulation Figure 3-1 Feedback Implementation of Secondary Side Regulation