Light emitting diode driver circuit with shunt switch

A LED driver circuit for controlling the amount of light generated by one or more serially connected Light-Emitting Diodes (LEDs), comprising:

• an output terminal for supplying an output voltage to the one or more serially connected LEDs;
• a feedback terminal for receiving a feedback signal from the one or more serially connected LEDs;
• an input terminal for receiving a control signal;
• an output circuit including means for generating said output voltage in accordance with a predetermined relationship between said control signal and said feedback signal when said control signal has a first predetermined voltage level, whereby said one or more serially connected LEDs are driven to generate visible light, and
• a shunt circuit including a transistor having a first terminal coupled to the output terminal, a second terminal coupled to the feedback terminal, and a control terminal coupled to the input terminal.

An LED display comprising:

• one or more serially connected Light-Emitting Diodes (LEDs);
• and
• an LED driver circuit for controlling the amount of light generated by said one or more LEDs, the LED driver circuit comprising:
• an output terminal for supplying an output voltage to the one or more serially connected LEDs;
• a feedback terminal for receiving a feedback signal from the one or more serially connected LEDs;
• an input terminal for receiving a control signal;
• output means for generating said output voltage in accordance with a predetermined relationship between said control signal and said feedback signal when said control signal has a first predetermined voltage level, whereby said one or more serially connected LEDs are driven to generate visible light, and
• shunt means for coupling said output terminal to said feedback terminal when said control signal has a second predetermined voltage level, whereby said output terminal and said feedback terminal are maintained at a substantially common voltage.