LED display systems
An LED display system comprises an LED array and an LED driver circuit. An LED driver circuit comprises components including a phase lock loop, a pulse width modulation engine, a configuration register, a series of gain adjustable fast charge current sources, and a serial input/output interface. The components in this driver circuit may be integrated on a same chip. The LED array may be arranged in a common cathode configuration.
1. A driver circuit for LEDs, comprising:
a phase lock loop;
a pulse width modulation engine;
a configuration register;
a gain adjustable fast charge current source;
a DOT correction adjustment means for adjusting an output current to an LED; and
a serial input/output interface,
wherein the phase lock loop, operatively connected to the serial input/output interface, provides a global clock signal,
wherein the pulse width modulation engine, operatively connected to the serial input/output interface, receives gray scale values from the serial input/output interface and the global clock signal from the phase lock loop, and generates a PWM signal for the gain adjustable fast charge current source,
wherein the configuration register, operatively connected to the serial input/output interface and the gain adjustable fast charge current source, stores driver circuit settings,
wherein the gain adjustable fast charge current source, operatively connected to the configuration register, the serial input/output interface, and the pulse width modulation engine, provides a current output to drive an LED array, and
wherein the serial input/output interface, operatively connected to the phase locked loop, the configuration register, the pulse width modulation engine, and the gain adjustable fast charge current sources, provides driver circuit settings to the configuration register, provides gray scale values to the pulse width modulation engine, and provides global gain adjustment settings to the gain adjustable fast charge current source.
2. The driver circuit according to claim 1 , further comprising a sink current return circuit for receiving a current from the LED array.
3. The driver circuit according to claim 1 , further comprising an error detection circuit, wherein the error detection circuit monitors a voltage drop across a LED.