Design changes Transformer wiring.pdfHelios 4000 PSU 24v 2.2 A.pdf
Good Afternoon
I have built the Standard webbench design for a 24v 2A power supply
I have several questions
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The transformer data
1. Lpri 4.8E-4H
2. Inductance Factor(AI) 114.0nH
3. Npri 65.0
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1.
On checking the transformer with the 10 turns method i get 166 uH divide this by 100 ie 10 Squared that would be 0.000000166 nH per turns squared
therefore 65 squared = 4225 times 0.000000166nH = 0.0070135 7.0125 mH ?? for the primary winding ? Webench suggests 4.8mH (see transformer data above)
I have checked the Inductance with an HP4263B
----Core Data as recommended --------------------------------------------------------------------
Un-gapped
Material A|_ value
N87 2050 +30/-20% 1610 < 2.6 (200 mT, 100 kHz, 100 °C) B66423G0000X187
2.
How do you arrive at a value of Al 2050 this would suggest 0.000002050 nH Turns Squared / 55^ = 4225 times 2050 nH = 0.00866125 = 8.66 mH for the primary
Hope this is clear
Thanks Bill
