Inductively coupled ballast circuit
First Claim
1. A ballast circuit, comprising:
- a control circuit;
an oscillator electrically connected with said control circuit, wherein said oscillator is activated in response to predetermined electric signals from said control circuit;
a driver electrically connected with said oscillator, wherein the output from said oscillator controls said driver;
a half-bridge switching circuit electrically connected with said driver, wherein the output of said driver controls said half-bridge switching circuit;
a series resonant tank circuit electrically connected with said half-bridge switching circuit, wherein said series resonant tank circuit includes an inductive coupler;
a secondary coil inductively coupled with said series resonant tank circuit, wherein said series resonant tank circuit inductively energizes said secondary coil; and
a load electrically connected to said secondary coil, whereby power is provided to said load by said secondary coil.
2 Assignments
0 Petitions
Accused Products
Abstract
A ballast circuit is disclosed for inductively providing power to a load. The ballast circuit includes an oscillator, a driver, a switching circuit, a resonant tank circuit and a current sensing circuit. The current sensing circuit provides a current feedback signal to the oscillator that is representative of the current in the resonant tank circuit. The current feedback signal drives the frequency of the ballast circuit causing the ballast circuit to seek resonance. The ballast circuit preferably includes a current limit circuit that is inductively coupled to the resonant tank circuit. The current limit circuit disables the ballast circuit when the current in the ballast circuit exceeds a predetermined threshold or falls outside a predetermined range.
439 Citations
12 Claims
-
1. A ballast circuit, comprising:
-
a control circuit;
an oscillator electrically connected with said control circuit, wherein said oscillator is activated in response to predetermined electric signals from said control circuit;
a driver electrically connected with said oscillator, wherein the output from said oscillator controls said driver;
a half-bridge switching circuit electrically connected with said driver, wherein the output of said driver controls said half-bridge switching circuit;
a series resonant tank circuit electrically connected with said half-bridge switching circuit, wherein said series resonant tank circuit includes an inductive coupler;
a secondary coil inductively coupled with said series resonant tank circuit, wherein said series resonant tank circuit inductively energizes said secondary coil; and
a load electrically connected to said secondary coil, whereby power is provided to said load by said secondary coil. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for supplying power to a load through an inductive coupling, comprising the steps of:
-
applying a signal at a frequency to a primary coil of an inductive coupling;
monitoring at least one characteristic of the signal applied to the primary; and
adjusting the frequency of the signal applied to the primary as a function of the monitored characteristic of the signal applied to the primary. - View Dependent Claims (12)
-
Specification