Practical AC Drive Circuitry For LEDs

This chapter addresses AC drive circuitry for LEDs. When LED light needs to run off the electrical grid, AC drive circuitry is used. AC power conversion is considerably more complicated than DC. The chapter discusses one of the important safety techniques to be used in the lab: isolating the system from AC line with an isolation transformer. Isolation is also very useful for products for the same reason, although it's not done the same way. The chapter discusses how to select the values of the components. One of the things that make design of AC ballasts much harder than DC is electromagnetic interference (EMI). Governments require that devices that attach to the AC line not produce more than a specific amount of electrical noise. And switch‐mode power supplies, since they switch at high frequency, generate a lot of noise. The chapter describes how to get AC converter to pass EMI.