| Electronic Components Datasheet Search |
|
AN4213 Datasheet(PDF) 20 Page - STMicroelectronics |
|
|
|||||||||||||||||||||||||||||
AN4213 Datasheet(HTML) 20 Page - STMicroelectronics |
|
20 / 42 page ![]() Designing a TM PFC AN4213 20/42 DocID023984 Rev 2 The maximum main-auxiliary winding turn ratio, nmax, has to ensure that the voltage delivered to the pin during the OFF-time of the Power MOSFET is sufficient to arm the ZCD circuit. Equation 36 The minimum value of the limiting resistor can be found assuming 0.8 mA current through the pin and considering the maximum voltage across the auxiliary winding with a selected turn ratio n = 10. The actual value can be fine-tuned in order to make the turn-on of the Power MOSFET occur exactly on the valley of the drain voltage oscillation (the boost inductor, completely discharged, is ringing with the drain capacitance, as shown in the figure below). This will minimize the power dissipation at turn-on. Figure 10. Optimum Power MOSFET turn-on Equation 37 Equation 38 7 . 15 15 . 1 4 . 1 2 max sec ≤ ∗ − ≤ ≤ n V V n n n AC OUT ondary primary AM17324v1 Vout Vdrain Vipk Vzcd 5.7 0.7 1.4 t t Ω = − = − = k mA mA V n V R ZCDH out 9 . 42 8 . 0 7 . 5 10 400 8 . 0 1 Ω = − ∗ = − = k mA mA V n V R ZCDL AC 8 . 46 8 . 0 0 10 265 2 8 . 0 2 max 2 |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |