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US 12,183,261 B2Granted
Video wall, driver circuits, controls and method thereof
AssigneeOSRAM Opto Semiconductors GmbH
InventorsThorsten Baumheinrich, Christopher Soell
Life of this patent
Estimating the term…
Abstract
The invention relates to various driver circuits, controls and arrangements for supplying loads, in particular light-emitting diodes, displays or even video walls.
Claims16
A supply circuit, comprising:
- an error correction detector with a reference signal input, an error signal input and a correction signal output, the error correction detector configured to provide a correction signal at the correction signal output in response to a reference signal at the reference signal input and a signal at the error signal input;
- a controllable current source having a current output and a control signal terminal, the control signal terminal being connected to the correction signal output to form a control loop for the controllable current source, wherein the controllable current source is adapted to provide a current at the current output in response to a signal at the control signal terminal;
- a substitute source having an output and being adapted to provide a substitute signal;
- and
- a switching device which is configured to supply, as a function of a switching signal, either a signal derived from the current at the current output or the substitute signal to the error signal input with additional isolation of the current output from the controllable current source, wherein the switching device includes a first input terminal coupled to the current output of the controllable current source, a second input terminal coupled to the output of the substitute source, and an output terminal coupled to the error signal input of the error correction detector.
2 more elements
A method of powering an LED, comprising:
- detecting a supply current through the LED;
- switching a switch to connect an output terminal to a first input terminal coupled to a current output associated with the supply current or a second input terminal coupled to a substitute output;
- comparing, in response to the switch connecting the output terminal to the first input terminal, the supply current with a reference signal and deriving a correction signal from the comparing, wherein an error correction detector is configured to derive the correction signal at a correction signal output in response to the reference signal at a reference signal input and a signal at an error signal input;
- changing the supply current in response to the correction signal to control the supply current to a reference point;
- and
- switching off the supply current through the LED and simultaneously supplying a substitute signal for the comparing by switching the switch to connect the output terminal to the second input terminal.
3 more elements
Dependencies are inferred from the claim text.