Patent ID: 6693387
Filing Date: 2004-02-17
Classification: H05B,Y02B

Abstract:
An electroluminescent driver circuit comprising:a load to provide illumination; an inductor having a first side coupled to a positive terminal of a power supply and a second side selectively coupled to the load; a transistor coupled to selectively conduct current from the second side of the inductor to a ground terminal of the power supply in response to a digital signal; a plurality of switches coupled to the load to selectively charge and discharge the load, wherein the switches selectively provide a discharge path for positive charge on the load to be discharged to the positive terminal of the power supply; wherein the plurality of switches further comprise; a first switch coupled between a connection between the second side of the inductor and the transistor and a first electrode of the load; a second switch coupled between the connection between the second side of the inductor and the transistor and the second electrode of the load; a third switch coupled between the first electrode of the load and ground; and a fourth switch coupled between the second electrode and ground, wherein when the third and fourth switches are closed, charge on the respective first or second electrodes of the load is discharged to the positive terminal of the power supply.