A simplified Neumann's formula for calculation of inductance of spiral coil

The state of the art design of switching mode power supply relies heavily on soft switching technique, which makes use of stray capacitance of active switch and leakage inductance of transformer to form a resonant tank, therefore the calculation of inductance of magnetic component is important. In this paper, a simplified Neumann's formula is proposed to calculate the inductance of spiral coil, which requires cumbersome and tedious calculation in the usual manner.