Patent ID: 11895748
Assignee: LUMILEDS, LLC
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 16:
17. A control circuit for a light emitting diode (LED) pixel comprising:
a close loop circuit configured to receive a current control signal and output an LED current regulating signal based on the current control signal, the close loop circuit comprises an operational amplifier (op-amp) having a first input, a second input, and an output, the first input coupled to a reference current transistor; and
a switching circuit configured to output an LED current according to a pulse width modulation (PWM) signal, the LED current having an amplitude regulated by the LED current regulating signal received from the close loop circuit, the switching circuit further configured to provide feedback to the close loop circuit for regulating the LED current, the second input coupled to the switching circuit to receive the feedback signal, and the output coupled to an input of the switching circuit, the switching circuit comprises a switching circuit transistor having a gate voltage set by the output of the op-amp, the switching circuit transistor and the reference current transistor are electrically coupled only through the op-amp and ground.