DocID027372 Rev 1

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AN4647

Final recommendation

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maximal voltage without opening is 24 V with -30 °C and 21 V with 85 °C ambient

temperature.

For USB port charger (5 V), the maximum capacitor without opening is 4.7 µF with a 2 V

secure margin.

4

Final recommendation

Taken into account USB grid charger results and USB port charger, ST recommends not

exceeding 4.7 µF capacitor on mobile device after CBTVS2Axx-1F3 on Vbus. A 30% secure

margin on voltage is then present.

For other voltages, Figure 5 presents maximal capacitor value.