Circuitry for current regulated, externally controlled LED driving

Patent metadata

Field	Value
Publication number	US-8933640-B2
Application number	US-201313735884-A
Country	US
Kind code	B2
Filing date	Jan 7, 2013
Priority date	Jan 7, 2013
Publication date	Jan 13, 2015
Grant date	Jan 13, 2015

Abstract

A current driver circuit for regulating a light emitting diode (LED) is disclosed. An example driver circuit uses one input node of the driver circuit for controlling both maximum brightness and dimming of an LED coupled to an output node of the driver circuit. The driver circuit supplies a reference voltage (VREF) to its input node. A microcontroller is coupled through a resistor or other resistive component to the input node of the driver circuit and provides the input current, where the input current is adjustable by the resistor value. The driver circuit is configured to drive multiple times the input current from its output node. By adjusting the resistor value the output current of the LED is adjusted. The microcontroller is configured to provide pulse width modulation (PWM). By reducing the duty cycle of the PWM waveform the dimming of the LED can be controlled.

First claim

what is claimed is:

1. A current driver circuit comprising:
an input node adapted to receive an input current;
an output node adapted to drive an output current;
a solid voltage module having a first input coupled to a reference voltage and a second input coupled to the input node, the solid voltage module including an operational amplifier having a non-inverting node coupled to the reference voltage and an inverting node coupled to the input node, the operational amplifier co…

Assignees

• Atmel Corp

Inventors

• Noller Armin

Classifications

• H03K3/00

  Electricity · mapped topic

• H03K17/00

  Electricity · mapped topic

• H05B37/02 Primary

  Electricity · mapped topic

• Y02B20/30

  Cross-Sectional Technologies · mapped topic

• H05B45/397

  Electricity · mapped topic