Battery charging circuit and method for reducing heat generated by the circuit during inactive periods
First Claim
Patent Images
1. A battery charging circuit comprising:
- a transformer having a primary winding and a secondary winding;
a light emitting device electrically connected to said secondary winding of said transformer, said light emitting device being configured to generate light in response to current conducted through said secondary winding of said transformer; and
a light-dependent resistor having a variable resistance electrically connected to said primary winding of said transformer, said light-dependent resistor being positioned to receive said light generated by said light emitting device to change said variable resistance of said light-dependent resistor so that current conducted through said primary winding of said transformer is decreased in response to said light to reduce the amount of heat generated by said primary winding of said transformer.
1 Assignment
0 Petitions
Accused Products
Abstract
A transformer-based battery charging circuit and method for reducing heat generated by the circuit during inactive periods uses a light emitting device, which is electrically connected to the secondary winding of a transformer, and a light-dependent resistor, which is electrically connected to the primary winding of the transformer, to decrease the current conducted through the primary winding of the transformer during the inactive periods.
12 Citations
20 Claims
-
1. A battery charging circuit comprising:
-
a transformer having a primary winding and a secondary winding;
a light emitting device electrically connected to said secondary winding of said transformer, said light emitting device being configured to generate light in response to current conducted through said secondary winding of said transformer; and
a light-dependent resistor having a variable resistance electrically connected to said primary winding of said transformer, said light-dependent resistor being positioned to receive said light generated by said light emitting device to change said variable resistance of said light-dependent resistor so that current conducted through said primary winding of said transformer is decreased in response to said light to reduce the amount of heat generated by said primary winding of said transformer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A battery charging circuit comprising:
-
a transformer having a primary winding and a secondary winding;
a first current path through said primary winding of said transformer, said first current path including input terminals to be connected to a power source;
a second current path through said secondary winding of said transformer, said second current path including output terminals to be connected to a battery to be charged;
a light emitting device electrically connected to said secondary winding of said transformer on said second current path, said light emitting device being configured to generate light in response to current conducted through said secondary winding of said transformer; and
a light-dependent resistor having a variable resistance electrically connected to said primary winding of said transformer on said first current path, said light-dependent resistor being positioned to receive said light generated by said light emitting device to change said variable resistance of said light-dependent resistor so that current through said primary winding of said transformer is decreased to reduce the amount of heat generated by said primary winding during inactive periods when said battery is not connected to said output terminals. - View Dependent Claims (10, 11, 12, 13, 14, 15)
-
-
16. A method for reducing heat generated in a transformer-based battery charging circuit during inactive periods, said method comprising;
-
removing a battery from said battery charging circuit;
changing the intensity of light generated by a light emitting device of said battery charging circuit in response to said removing of said battery; and
changing the resistance of a light-dependent resistor of said battery charging circuit in response to said changing of said intensity of light, including decreasing current conducted through a transformer of said battery charging circuit to reduce the amount of heat generated by said transformer of said battery charging circuit. - View Dependent Claims (17, 18, 19, 20)
-
Specification