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US 12,744,001 B2Granted
Data driver for display and sensing circuit thereof
AssigneeLx Semicon Co., Ltd.
InventorsYoung Ho Shin, Won Kim, Seong Geon Kim, Taiming Piao, Byeon Cheol Lee
Life of this patent
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Abstract
An embodiment provides a data driver for a display and a sensing circuit thereof, and the sensing circuit comprises: an analog front end circuit which generates an input voltage; a sample-and-hold circuit which stores a first sampling voltage according to the input voltage and generates a second sampling voltage obtained by converting the first sampling voltage; and an amplifier circuit which generates a sensing voltage according to the second sampling voltage.
Claims15
A sensing circuit comprising:
- an analog front end circuit configured to generate an input voltage corresponding to a pixel voltage of a sensed pixel;
- a sample-and-hold circuit configured to store a first sampling voltage corresponding to a first voltage difference between the input voltage and a first reference voltage at a first time point, generate a second sampling voltage by converting the first sampling voltage using a second reference voltage at a second time point after the first time point, and output the second sampling voltage, wherein the sample-and-hold-circuit comprises a first capacitor connected between a first node and a second node to which the input voltage is transmitted and a second capacitor connected between the first node and a third node to which the first reference voltage is transmitted, wherein the second sampling voltage is a voltage difference between the second node and the third node, and wherein the sample-and-hold circuit is configured to maintain linearity of the second sampling voltage;
- and
- an amplification circuit configured to amplify the second sampling voltage to generate a sensing voltage,
- wherein the input voltage is higher than the first reference voltage and the second reference voltage, and the first reference voltage is lower than the second reference voltage,
- wherein the amplification circuit comprises an amplifier, at least one offset capacitor and at least one feedback capacitor, and is configured to form a feedback loop that includes the at least one feedback capacitor connected in series with at least one sampling capacitor of the sample-and-hold circuit, and
- wherein an offset voltage stored on the at least one offset capacitor before the amplification is configured to be applied with opposite polarity to an offset voltage at an input terminal of the amplifier to cancel the offset voltage during the amplification of the second sampling voltage.
4 more elements
A data driver comprising:
- an analog front end circuit configured to generate an input voltage corresponding to a pixel voltage of a sensed pixel;
- a sample-and-hold circuit configured to store a first sampling voltage corresponding to the input voltage using a first reference voltage at a first time point and output a second sampling voltage obtained by converting the first sampling voltage using a second reference voltage at a second time point after the first time point, wherein the sample-and-hold circuit is configured to store the first sampling voltage corresponding to a first voltage difference between the input voltage and the first reference voltage, generate the second sampling voltage by converting the first sampling voltage using the second reference voltage, and output the second sampling voltage, wherein the sample-and-hold-circuit comprises a first capacitor connected between a first node and a second node to which the input voltage is transmitted and a second capacitor connected between the first node and a third node to which the first reference voltage is transmitted, wherein the second sampling voltage is a voltage difference between the second node and the third node, and wherein the sample-and-hold circuit is configured to maintain linearity of the second sampling voltage;
- an amplification circuit configured to amplify the second sampling voltage to generate a sensing voltage;
- and
- an analog-to-digital converter configured to output a digital signal corresponding to the sensing voltage,
- wherein the amplification circuit comprises an amplifier, at least one offset capacitor and at least one feedback capacitor, and is configured to form a feedback loop that includes the at least one feedback capacitor connected in series with at least one sampling capacitor of the sample-and-hold circuit, and
- wherein an offset voltage stored on the at least one offset capacitor before the amplification is configured to be applied with opposite polarity to an offset voltage at an input terminal of the amplifier to cancel the offset voltage during the amplification of the second sampling voltage.
4 more elements
Dependencies are inferred from the claim text.