Design and optimization of a linear voice coil motor for LED die bonders

In this paper, a direct drive implementation scheme using a linear voice coil motor (VCM) is proposed and designed for LED die bonding application. Design specifications are obtained by real requirements. Finite element analysis of electromagnetic field is used to design the VCM. A prototype VCM was manufactured. The performance is evaluated experimentally and compared with that produced by simulation. To improve the design, a mathematical model of electromagnetic force in the voice coil motor is derived. An analytical optimization formulation is proposed to maximize the total force constants along a given stroke given constraints on motor size. This leads to a great improvement both in size and force performance.