Patent ID: 9677533
Date: 2017-06-13
CPC Classifications: F02P,H01S

Claim:
1. An apparatus for operating at least one light-emitting diode in a form of a laser diode, the apparatus comprising: a current-regulating circuit for regulating a current running through the at least one light-emitting diode, said current-regulating circuit having an actuator being a controllable semiconductor element with a load section, the light-emitting diode being interconnected in series with said load section of said controllable semiconductor element; a voltage-regulating circuit having first and second supply voltage terminals being output connections of said voltage-regulating circuit, said voltage-regulating circuit being a DC voltage boost converter outputting a supply voltage; and a current measuring resistor connected between said first supply voltage terminal and said second supply voltage terminal; said current-regulating circuit having a storage coil, a first regulator and a freewheeling element; and wherein said current-regulating circuit is a switched buck converter, said load section of said controllable semiconductor element is interconnected in series with said storage coil between said first supply voltage terminal and an anode of the at least one light-emitting diode and said freewheeling element is connected between a connecting node between said controllable semiconductor element and said storage coil and said second supply voltage terminal, said first regulator is connected to a control connection of said controllable semiconductor element and that connection of said current measuring resistor which is not connected to said second supply voltage terminal.