SLVAEQ2 April   2020 TPS2549-Q1 , TPS254900-Q1 , TPS254900A-Q1 , TPS2556-Q1 , TPS2557-Q1 , TPS2559-Q1 , TPS25830-Q1 , TPS25831-Q1 , TPS25832-Q1 , TPS25833-Q1 , TPS25840-Q1 , TPS25842-Q1

 

  1.   How to Pass MFi Overcurrent Protection Test With USB Charger and Switch Device
    1.     Trademarks
    2. 1 The Instruction of MFi OCP Requirement
    3. 2 Test Standard and Requirements
    4. 3 The Solution to Pass MFi OCP Test
      1. 3.1 Solution 1: Increasing Current Limit Point Higher Than 1.6*Ia
      2. 3.2 Solution 2: Paralleling RC With Rlimit to Delay the Current Limit Response
        1. 3.2.1 For the 1.5A USB Port With External FET
        2. 3.2.2 For the 1.5A Port Without External FET
        3. 3.2.3 For 2.1A USB Port With External FET
        4. 3.2.4 For 2.1A USB Port Without External FET
        5. 3.2.5 For 2.4A USB Port With External FET
        6. 3.2.6 For 2.4A USB Port Without External FET
        7. 3.2.7 For 3A USB Port With External FET
        8. 3.2.8 For 3A USB Port Without FET
    5. 4 Summary
    6. 5 References

For 2.1A USB Port Without External FET

For 2.1A USB port, set the current limit to 2.52A without external FET, parallel 15.8kΩ + 82 nF RC with a 15.8kΩ Rlimit. The Vcsn does not have any drop under the certification load.

figure 17.tifFigure 14. Set 2.52A Current Limit for 2.1A Port Without External FET