Maximum Flux Density Calculator

The maximum flux density for a core/coil geometry should be calculated to verify that it is below the specified value for a given core, so that the core doesn't saturate. This calculator is useful in matching a core size to the required power.

Note that if there is no DC term, then the calculation is completely independent of the core material.

AC Terms
Vrms	(Vrms)
F (frequency, use the minimum frequency that the coil will see)	(MHz)
N (Number of turns)
Ac (Equivalent area - the cross section of core)	(cm2)
Optional DC Terms.
Idc (DC current through winding. This is optional)	(A)
L (Specific to core used. Only enter if, coil has DC)	(uH)
Bmax	(gauss)

Equations

B_max=B_max(AC)+B_max(DC)

B_max(DC)= (L*I_dc*10⁸)/(NA_c)

B_max= (V_rms*10⁸)/(4.44*F*N*A_c) + (L*I_dc*10⁸)/(N*A_c) gauss

Note if no DC current flows, then the second term of the equation is dropped.

In terms of A_L(uH/100T²₎:

L= N²A_L(uH/100T²₎10^-4

B_max(DC)= (N*A_L(uH/100T²₎10⁴*I_dc)/(A_c)