Patent · US Active

LED driver circuit

US10694603B1 · kind B1 · utility

1Cited by

9References

20Claims

0Family size

Assignee

Apple Inc. · US

Inventors

Cristian Grecu · Munich, DE
Bogdan-Eugen Matei · Westerndorf, DE
Angelo Bassi · Munich, DE
Andrei-Cosmin Gaidam · Munich, DE
Alessandro Molari · Eichenau, DE

Key dates

Filing date	Nov 14, 2019
Grant date	Jun 23, 2020
Priority date	—
Expiry date	Nov 14, 2039

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02B20/30
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

An LED driver circuit is disclosed. The LED driver circuit includes an amplifier having a first input coupled to receive a reference voltage and a second input coupled to receive a feedback voltage. The circuit further includes first and second transistors each having respective gate terminals coupled to an output of the first amplifier. In a first mode, a first switch alternately couples a source terminal of the first transistor to the second input of the amplifier (when the pulse is asserted) and a source terminal of the second transistor to the second input (when the pulse is de-asserted). A third transistor includes a gate terminal that is coupled to ground, by a second switch, when operating in the first mode. When operating in the second mode, the switch couples the third transistor to the output of the amplifier, while the pulse remains asserted.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.