The UC3872 is a resonant lamp ballast controller optimized for driving cold cathode fluorescent, neon, and other gas discharge lamps. The resonant power stage develops a sinusoidal lamp drive voltage, and minimizes switching loss and EMI generation. Lamp intensity adjustment is accomplished with a buck regulator, which is synchronized to the external power stage's resonant frequency. Suitable for automotive and battery powered applications, the UC3872 draws only 1A when disabled.