Patent ID: 7385357
Filing Date: 2008-06-10
Classification: A61L,C02F,H01F,H02J,H05B,Y02B

Abstract:
1. A ballast circuit comprising: a primary subcircuit having a primary coil; a current sensor connected to said primary subcircuit, said current sensor sensing a characteristic of a current in said primary subcircuit; a control circuit supplying current to said primary coil, said control circuit varying a characteristic of the current supplied to said primary coil as a function of said characteristic sensed by said current sensor; a secondary coil inductively coupled with said primary coil, wherein said primary coil inductively energizes said secondary coil; a load electrically connected to said secondary coil, whereby power is provided to said load by said secondary coil; and an oscillator including a buffer circuit that prevents load changes from pulling the frequency of oscillation of said oscillator.