Backlight control circuit with micro controller feeding operating state of load circuit back to pulse width modulation integrated circuit
AssigneesInnocom Technology (Shenzhen) Co., Ltd., Chimei Innolux Corporation
InventorsHong-Ren Wang, Yi-Hsiang Kao
Life of this patent
Estimating the term…
Abstract
An exemplary backlight control circuit (200) includes at least one load circuit (210), a pulse width modulation integrated circuit (250), and a micro controller (260). The micro controller includes an output terminal and a plurality of analog to digital input terminals. The output terminal outputs a high level signal when the analog to digital input terminals all receive high level signals, and the output terminal outputs a low level signal when any one of the analog to digital input terminals receives a low level signal. The micro controller feeds operating states of the at least one load circuit back to the pulse width modulation integrated circuit.
Claims10
A backlight control circuit, comprising:
- at least one load circuit, each comprising a lamp and an output terminal, the output terminal outputting a high voltage when the lamp being in a normal working state, and outputting a low voltage when the lamp being in an open circuit state or a short circuit state;
- a pulse width modulation integrated circuit comprising a current sampling pin, the pulse width modulation integrated circuit configured to stop working if the current sampling pin having a low voltage;
- a micro controller comprising an output terminal and a plurality of analog to digital input terminals, the output terminal outputting a high level signal when the analog to digital input terminals all receiving high level signals, and the output terminal outputting a low level signal when any one of the analog to digital input terminals receiving a low level signal;
- wherein the output terminal of each load circuit is connected to a corresponding analog to digital input terminal of the micro controller, the output terminal of the micro controller is connected to the current sampling pin of the pulse width modulation integrated circuit.
A backlight control circuit, comprising:
- at least one load circuit;
- a pulse width modulation integrated circuit, the pulse width modulation integrated circuit comprises comprising a current sampling pin, the pulse width modulation integrated circuit configured to stop working if the current sampling pin has a low voltage;
- and
- a micro controller comprising an output terminal and a plurality of analog to digital input terminals, the output terminal outputting a high level signal when the analog to digital input terminals all receiving high level signals, and the output terminal outputting a low level signal when any one of the analog to digital input terminals receiving a low level signal;
- wherein the micro controller feeds operating states of the at least one load circuit back to the pulse width modulation integrated circuit.
Dependencies are inferred from the claim text.