Apr 172012
Push image to enlarge
|
|
|
|
InfoThe first approximation is based on a modification of an expression developed by Wheeler; the second is derived from electromagnetic principles by approximating the sides of the spirals as current-sheets; and the third is a monomial expression derived from fitting to a large database of inductors (and the exact inductance values).
All three expressions are accurate, with typical errors of 2 – 3%, and very simple, and are therefore excellent candidates for use in design and synthesis. The thickness of the inductor has only a very small effect on inductance and will therefore be ignored.
Notes:
Push “Defaults” button to fill in some values.Then push “calculate”.
1μm =0.001mm
1μm =0.00003937007874015748 inch
Push “Defaults” button to fill in some values.Then push “calculate”.
1μm =0.001mm
1μm =0.00003937007874015748 inch
Reference:
S.S. Mohan, M. Hershenson, S.P. Boyd and T.H. Lee
Simple Accurate Expressions for Planar Spiral Inductances
IEEE Journal of Solid-State Circuits, Oct. 1999, pp. 1419-24.
For multilayer spiral pcb coils see here:
A new calculation for designing multilayer planar spiral inductors
S.S. Mohan, M. Hershenson, S.P. Boyd and T.H. Lee
Simple Accurate Expressions for Planar Spiral Inductances
IEEE Journal of Solid-State Circuits, Oct. 1999, pp. 1419-24.
For multilayer spiral pcb coils see here:
A new calculation for designing multilayer planar spiral inductors
![]()
If you find this page useful for others, please consider sharing it




