Circuit and method for a hybrid heater with dual function heating capability

1. A method of fusing toner to sheets of media in an imaging device, comprising:

providing a fuser heater having a first heating element and a second heating element;

during a warm up operation, passing current through the first heating element to generate heat thereby;

determining a width of at least one media sheet having toner to be fused;

upon determining that the width of the at least one media sheet is less than a predetermined width, passing current through the second heating element during a fusing operation for the at least one media sheet following the warm up operation to generate heat by the second heating element, and ceasing passing current through the first heating element;

upon determining that the width of the at least one media sheet is greater than the predetermined width, continuing to pass current through the first heating element during the fusing operation and refraining from passing current through the second heating element during the fusing operation.

2. The method of claim 1 , further comprising passing current through the second heating element during the warm up operation so as to generate heat by the first and second heating elements.

3. The method of claim 1 , further comprising determining a temperature in the imaging device and upon determining that the temperature is below a predetermined temperature, passing current through the second heating element during the warm up operation so as to generate heat by the first and second heating elements.

4. A heat control system for fusing toner to sheets of media, comprising:

a fuser heater comprising a first heating element and a second heating element, the fuser heater providing heat to a fuser nip;

heat control circuitry coupled to the fuser heater for passing current through the first and second heating elements of the fuser heater to generate heat therefrom; and

a controller coupled to the heat control circuitry for controlling the heat control circuitry, the controller configured to control the heat control circuitry for passing current through the first heating element during a warm up operation, determine whether a width of at least one media sheet to be fused is less than a predetermined width, upon an affirmative determination control the heat control circuitry for passing current through the second heating element during a fusing operation following the warm up operation, the fusing operation fusing toner the at least one media sheet, and upon a negative determination, control the heat control circuitry for passing current through the first heating element while not passing current through the second heating element during the fusing operation.

5. The heat control system of claim 4 , wherein the first heating element comprises at least one resistive trace.

6. The heat control system of claim 5 , wherein the second heating element comprises a positive thermal coefficient material.

7. The heat control system of claim 4 , wherein the controller controls the heat control circuitry to cease passing current through the first heating element during the fusing operation based upon the affirmative determination.

8. The heat control system of claim 4 , wherein the controller is further configured to control the heat control circuitry to pass current through the second heating element during the warm up operation so as to generate heat by the first and second heating elements.

9. The heat control system of claim 4 , wherein the controller is further configured to determine whether a temperature of the heat control system is below a predetermined temperature during the warm up operation, and based upon an affirmative determination, control the heat control circuitry to pass current through the second heating element during the warm up operation so as to generate heat by the first and second heating elements.

10. The heat control system of claim 4 , wherein the controller controls the heat control circuitry so that no current is passed through the second heating element during the warm up operation.

11. An imaging device for fusing toner to sheets of media, comprising:

a fuser housing;

a fuser heater disposed substantially within the fuser housing, the fuser heater comprising a first heating element and a second heating element;

a fusing belt rotatably positioned about the fuser housing such that the fuser heater provides heat to the fusing belt;

a backup member disposed substantially against the fusing belt, the backup member and the fusing belt forming a fuser nip;

heat control circuitry connected to the fuser heater for passing current through the first and second heating elements of the fuser heater to generate heat therefrom; and

a controller connected to the heat control circuitry, the controller controlling the heat control circuitry for passing current through the first heating element during a warm up operation, the controller configured to determine whether a sheet of media that is to undergo a fusing operation is less than a predetermined width, upon an affirmative determination control the heat control circuitry for passing current through the second heating element during the fusing operation following the warm up operation, the fusing operation fusing toner to the media sheet, and upon a negative determination control the heat control circuitry to pass current through the first heating element and to refrain from passing current through the second heating element during the fusing operation.

12. The imaging device of claim 11 , wherein the second heating element comprises a positive thermal coefficient material.

13. The imaging device of claim 11 , wherein upon a positive determination, controlling the heat control circuitry to to cease passing current through the first heating element during the fusing operation.

14. The imaging device of claim 11 , wherein the controller is further configured to control the heat control circuitry to simultaneously pass current through the first and second heating elements during the warm up operation so as to simultaneously generate heat by the first and second heating elements.

15. The imaging device of claim 11 , wherein the controller is further configured to determine whether a temperature in the imaging device is below a second predetermined temperature and based upon an affirmative determination, control the heat control circuitry to pass current through the second heating element during the warm up operation so as to simultaneously generate heat by the first and second heating elements.