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# V.us product of current snese transformer?

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#### cupoftea

Hi,
We wish to use the PA1005.100NTL (100:1) as a unipolar current sense transformer in our 350W Boost converter.
{Vin = 18V, vout = 58V, Fsw=100kHz, L =40uH}
The datasheet gives no V.us product.

It just gives B(max) = 37.59 x Vref x Dmax x 1E5 / N x Freq(kHz)

For us, Dmax = 0.7
Freq = 100kHz.
Controller = UCC28C43 (with current sense ref voltage of 1V)

So that means we have a peak B of 0.076T.

In the bold equation above (taken from datasheet), i took "Vref" to mean the peak voltage across the secondary coil.
Would you agree?

The thing is, that is not "Vref". The peak voltage across the secondary coil is V(sense_reference) + Vf + (Ipk/100) x R(sec).

So why are they using "Vref" in the bold equation above?

PA1005.100NTL

Read datasheet thoroughly. Vref corresponds to output voltage.

Thanks yes, but surely they should be considering the actual votlage across the secondary coil, not the "VREF".....i can see in the datasheet where they mark the "VREF".

In that equation , for some reason, they have ignored the voltage across the diode, and the voltage across the coil resistance.

True indeed, their VFEF based specification gives nevertheless an idea of saturation limits.

cupoftea

### cupoftea

Points: 2
use Vref = output of coil ( max )

cupoftea

Points: 2