Patent ID: 8786210
Filing Date: 2014-07-22
Classification: A61B,H05B,Y02B

Abstract:
1. A drive circuit for a light emitting diode, the drive circuit comprising: an input voltage and a ground; a current control block including a voltage supply connection, a ground connection, a first voltage sense connection, and a second voltage sense connection, the voltage supply connection electrically connected to the input voltage and the ground connection connected to the ground, the current control block configured to maintain a constant voltage across the first and second voltage sense connections; a current sense resistor connected to the first voltage sense connection; a first current adjustment resistor connected between the current sense resistor and the second voltage sense connection; and a second current adjustment resistor connected between the second voltage sense connection and the input voltage, thereby forming a voltage divider at the second voltage sense connection, such that adjustment of the input voltage proportionally changes a voltage across the light emitting diode at a constant current.