CN-122002662-A - Multicolor LED mixed color balance calibration circuit

Abstract

A circuit for multicolor LED hybrid color balance calibration includes an LED loop including one or more different color LED channels, each of the one or more different color LED channels including one or more same color LEDs and an LED switch, an LED junction configured to connect to the one or more different color LED channels, a voltage dividing resistor configured to connect between the LED junction and a color calibration switch, the color calibration switch configured to enable or disable color calibration based on a received color calibration enable signal, and a microprocessor configured to generate a color calibration enable signal, measure a first voltage at which each of the one or more different color LED channels at the LED junction is individually turned on based on the generated color calibration enable signal, and adjust a hybrid color output by the LED loop based on the measured first voltage.

Inventors

• FEI WEIHE

Assignees

• 施耐德电气工业公司

Dates

Publication Date

20260508

Application Date

20241107

Claims (11)

1. 1. A circuit for multicolor LED hybrid color balance calibration, the circuit comprising: An LED circuit comprising one or more different colored LED channels, each of the one or more different colored LED channels comprising one or more LEDs of the same color and an LED switch; An LED junction configured to connect to the one or more differently colored LED channels; A voltage dividing resistor configured to be connected between the LED junction and the color calibration switch; A color calibration switch configured to enable or disable color calibration based on the received color calibration enable signal, and A microprocessor configured to: a color calibration enable signal is generated and, Measuring a first voltage when each of the one or more differently colored LED channels at the LED junction is individually turned on based on the generated color calibration enable signal, and The mixed color of the LED loop output is adjusted based on the measured first voltage.
2. 2. The circuit of claim 1, wherein, The microprocessor is configured to send a turn-on signal of an LED switch corresponding to the one or more differently colored LED channels to an LED loop based on the color calibration enable signal.
3. 3. The circuit of claim 1, wherein, The microprocessor is configured to adjust a conduction pulse width of a conduction signal of an LED switch corresponding to the one or more different color LED channels based on the measured first voltage when each of the one or more different color LED channels is individually turned on.
4. 4. The circuit of claim 1, wherein, The color calibration switch enables color calibration when the received color calibration enable signal is high.
5. 5. The circuit of claim 1, wherein, The microprocessor is further configured to determine whether an LED short circuit occurs for each of the one or more differently colored LED channels at the LED junction based on a first voltage when the LED channel is individually turned on to turn off an LED switch corresponding to the LED channel determined to be shorted, according to the color calibration enable signal.
6. 6. The circuit of claim 1, wherein, The LED loop comprises N LED channels with different colors, wherein N is an integer greater than or equal to 2.
7. 7. The circuit of claim 1, wherein, Each of the one or more different color LED channels further includes one or more LED series resistors connected to a respective one of the one or more different color LEDs.
8. 8. The circuit of claim 1, wherein, The LED switches corresponding to the one or more different color LED channels are metal oxide semiconductor field effect transistor MOSFETs, and the gates of the respective LED switches receive from the microprocessor the on signals of the LED switches corresponding to the one or more different color LED channels.
9. 9. The circuit of any one of claims 1 to 8, wherein the circuit further comprises: an LED short circuit protection switch configured to be connected to an LED junction, and An LED short detection module configured to be connected to the LED junction and the LED short protection switch, measure a second voltage at the LED junction based on the received color calibration enable signal, and determine whether an LED short occurs to turn off or on the LED short protection switch based on the measured second voltage.
10. 10. The circuit of claim 9, wherein, The LED short-circuit protection switch is configured to conduct when the received color calibration enable signal is low, and the LED short-circuit detection module measures a second voltage at the LED junction.
11. 11. An electronic device, the electronic device comprising: Regulated power supply module, and The circuit of any preceding claim, configured to be connected to a regulated power supply module.

Description

Multicolor LED mixed color balance calibration circuit Technical Field The invention relates to a multicolor LED color mixing technology, in particular to a circuit for multicolor LED color mixing balance calibration. Background Light Emitting Diodes (LEDs) are an energy efficient, high brightness, small volume light source with very wide application in the fields of electrical devices, displays, lighting systems, etc. In an application scenario in which an LED is used as a backlight of a display, a multicolor LED such as RGB may be used as a light source, and various color effects may be presented to the backlight by color mixing driving, so as to achieve a color indication with a specific meaning. In the design of display multicolor backlight LEDs, in order to keep the mixed colors consistent between each display backlight, color balance compensation needs to be considered in the backlight driving design. In addition, how to safely use LEDs is an important issue in LED driving technology. Short-circuit faults can sometimes occur in the production and use processes of the LED lead, so that the LED short-circuit faults need to be effectively protected in the LED driving design, and burning of an LED driving power supply and even breakdown of a power supply system of the whole equipment are avoided. Disclosure of Invention The invention proposes a circuit for multicolor LED mixed color balance calibration, the circuit comprising an LED loop comprising one or more different color LED channels, each of the one or more different color LED channels comprising one or more same color LEDs and an LED switch, an LED junction configured to be connected to the one or more different color LED channels, a voltage dividing resistor configured to be connected between the LED junction and a color calibration switch, the color calibration switch configured to enable or disable color calibration based on a received color calibration enable signal, and a microprocessor configured to generate a color calibration enable signal, measure a first voltage at the LED junction when each of the one or more different color LED channels is individually turned on based on the generated color calibration enable signal, and adjust a mixed color output by the LED loop based on the measured first voltage. According to an embodiment of the invention, the microprocessor is configured to send on signals of the LED switches corresponding to one or more LED channels of different colors to the LED loop based on the color calibration enable signal. According to an embodiment of the invention, the microprocessor is configured to adjust the on pulse width of the on signal of the LED switch corresponding to the one or more different colored LED channels based on the measured first voltage when each of the one or more different colored LED channels is individually turned on. According to an embodiment of the present invention, the color calibration switch enables color calibration when the received color calibration enable signal is high. According to an embodiment of the invention, the microprocessor is further configured to determine whether an LED short circuit occurs in each of the one or more differently colored LED channels at the LED junction based on the first voltage when the LED channel is individually turned on to turn off the LED switch corresponding to the LED channel determined to be shorted. According to an embodiment of the invention, the LED loop comprises N LED channels of different colors, wherein N is an integer greater than or equal to 2. According to an embodiment of the invention, the one or more different colored LED channels further comprise one or more LED series resistors, the one or more LED series resistors being connected to a respective one of the one or more different colored LEDs. According to an embodiment of the invention, the LED switches corresponding to the one or more different color LED channels are metal oxide semiconductor field effect transistor MOSFETs, and the gates of the LED switches corresponding to the one or more different color LED channels receive from the microprocessor the on signal of the LED switches corresponding to the one or more different color LED channels. According to an embodiment of the invention, the circuit further comprises an LED short-circuit protection switch configured to be connected to the LED junction, and an LED short-circuit detection module configured to be connected to the LED junction and the LED short-circuit protection switch, to measure a second voltage at the LED junction based on the received color calibration enable signal, and to determine whether an LED short-circuit has occurred to switch the LED short-circuit protection switch off or on based on the measured second voltage. According to an embodiment of the invention, the LED short-circuit protection switch is configured to conduct when the received color calibration enable signal is low, and the LED short-circuit