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CN-122024617-A - Voltage buffer, voltage buffering method, display driving chip and electronic equipment

CN122024617ACN 122024617 ACN122024617 ACN 122024617ACN-122024617-A

Abstract

The application discloses a voltage buffer, a voltage buffering method, a display driving chip and electronic equipment, and belongs to the technical field of display. The voltage buffer comprises a voltage buffer module and an offset calibration module, wherein the voltage buffer module comprises a first output stage and a second output stage, the voltage buffer module is used for outputting a first output voltage to a load through the first output stage in a non-calibration mode or outputting a second output voltage to the offset calibration module through the second output stage in a calibration mode, and the offset calibration module is used for performing current compensation on the voltage buffer module based on the second output voltage under the condition that the second output voltage is received so as to calibrate direct current offset of the voltage buffer module. Therefore, the direct current offset of the voltage buffer module is calibrated in a current compensation mode, and the offset calibration speed is accelerated due to the fact that the second output voltage in the calibration mode is faster to build.

Inventors

  • PENG RUI
  • LI DONGMING
  • Jin Mencheng

Assignees

  • 北京奕斯伟计算技术股份有限公司

Dates

Publication Date
20260512
Application Date
20260320

Claims (18)

  1. 1. A voltage buffer, characterized in that the voltage buffer comprises a voltage buffer module and an offset calibration module, the voltage buffer module comprises a first output stage and a second output stage; The voltage buffer module is used for outputting a first output voltage to a load through the first output stage in a non-calibration mode or outputting a second output voltage to the offset calibration module through the second output stage in a calibration mode; And the offset calibration module is used for performing current compensation on the voltage buffer module based on the second output voltage under the condition that the second output voltage is received so as to calibrate direct current offset of the voltage buffer module.
  2. 2. The voltage buffer of claim 1, wherein the voltage buffer module further comprises an input stage; the voltage buffer module is further configured to receive an input voltage through the input stage and convert the input voltage into an intermediate voltage, where the intermediate voltage acts on the first output stage in the non-calibration mode to output a first output voltage to a load through the first output stage, or acts on the second output stage in the calibration mode to output a second output voltage to the offset calibration module through the second output stage.
  3. 3. The voltage buffer of claim 2 wherein the input stage comprises a positive input and a negative input, the input voltage being received by the positive input and the negative input, wherein the positive input is for receiving an electrical signal of input data, the negative input is for receiving the first output voltage in the non-calibration mode, and the negative input is for receiving the electrical signal of input data in the calibration mode.
  4. 4. The voltage buffer according to claim 1, wherein the voltage buffer is a first stage voltage buffer of two voltage buffers connected in series, and wherein the first stage voltage buffer enters the calibration mode when a second stage voltage buffer of the two voltage buffers completes calibration, and wherein an input voltage of the first stage voltage buffer is an output voltage of the second stage voltage buffer.
  5. 5. The voltage buffer of any of claims 1-4, wherein the offset calibration module comprises a logic control circuit and a current compensation circuit; The logic control circuit is used for determining whether to perform current compensation on the voltage buffer module based on the second output voltage, and sending a first signal to the current compensation circuit under the condition that the current compensation on the voltage buffer module is determined; The current compensation circuit is used for inputting compensation current to the voltage buffer module under the condition that the first signal sent by the logic control circuit is received.
  6. 6. The voltage buffer according to claim 5, wherein the current compensation circuit comprises N current sources connected in parallel, N being a positive integer greater than 1, the N current sources being connected to the first node through N first switches, one current source corresponding to each first switch, the N first switches being used to adjust the magnitude of the compensation current; The first node is connected with one end of a current mirror in the voltage buffer module through a second switch, the first node is connected with the other end of the current mirror through a third switch, and the second switch and the third switch are used for adjusting the input position of the compensation current.
  7. 7. The voltage buffer of claim 5, wherein the second output voltage is at a first level when the voltage buffer module has a dc offset, and is at a second level when the voltage buffer module has no dc offset; the logic control circuit is configured to determine to perform current compensation on the voltage buffer module when the second output voltage is at the first level, and determine not to perform current compensation on the voltage buffer module when the second output voltage is at the second level.
  8. 8. The voltage buffer according to any one of claims 1 to 4, wherein the voltage buffer is applied to a display driving chip, an operation phase of the display driving chip includes an active display period, an inactive display period, and a vertical blanking period, and the offset calibration module operates in the inactive display period or the vertical blanking period.
  9. 9. The voltage buffering method is applied to a voltage buffer, the voltage buffer comprises a voltage buffering module and an offset calibration module, the voltage buffering module comprises a first output stage and a second output stage, and the method comprises the following steps: In a non-calibration mode, outputting a first output voltage to a load through the first output stage of the voltage buffer module; or in a calibration mode, outputting a second output voltage to the offset calibration module through the second output stage of the voltage buffer module, and performing current compensation on the voltage buffer module through the offset calibration module based on the second output voltage so as to calibrate direct current offset of the voltage buffer module.
  10. 10. The method of claim 9, wherein the voltage buffer module further comprises an input stage, the method further comprising: The input voltage is received through the input stage of the voltage buffer module and converted into an intermediate voltage, the intermediate voltage acts on the first output stage in the non-calibration mode to output a first output voltage to a load through the first output stage, or acts on the second output stage in the calibration mode to output a second output voltage to the offset calibration module through the second output stage.
  11. 11. The method of claim 10, wherein the input stage comprises a positive input terminal and a negative input terminal, the input voltage being received through the positive input terminal and the negative input terminal, the receiving the input voltage through the input stage of the voltage buffering module comprising: receiving an electrical signal of input data through the positive input terminal; the first output voltage is received in the non-calibration mode through the negative input terminal, and the electric signal of the input data is received in the calibration mode through the negative input terminal.
  12. 12. The method of claim 9, wherein the voltage buffer is a first stage voltage buffer of two voltage buffers in series, the method further comprising: And under the condition that the second-stage voltage buffer of the two voltage buffers is calibrated, controlling the first-stage voltage buffer to enter the calibration mode, wherein the input voltage of the first-stage voltage buffer is the output voltage of the second-stage voltage buffer.
  13. 13. The method of any of claims 9-12, wherein the offset calibration module includes a logic control circuit and a current compensation circuit, wherein the current compensation of the voltage buffer module based on the second output voltage by the offset calibration module includes: Determining, by the logic control circuit, whether to current compensate the voltage buffer module based on the second output voltage, and sending a first signal to the current compensation circuit if it is determined to current compensate the voltage buffer module; And under the condition that the first signal sent by the logic control circuit is received, the current compensation circuit inputs compensation current to the voltage buffer module.
  14. 14. The method of claim 13, wherein the current compensation circuit comprises N current sources connected in parallel, N being a positive integer greater than 1, the N current sources being connected to the first node through N first switches, one current source corresponding to each first switch, the method further comprising: adjusting the magnitude of the compensation current by controlling the N first switches; the first node is connected with one end of a current mirror in the voltage buffer module through a second switch, and the first node is connected with the other end of the current mirror through a third switch, and the method further comprises the following steps: The input position of the compensation current is adjusted by controlling the second switch and the third switch.
  15. 15. The method of claim 13, wherein the second output voltage is at a first level when the voltage buffer module has a dc offset, and wherein the determining whether to current compensate the voltage buffer module based on the second output voltage comprises: and determining to perform current compensation on the voltage buffer module when the second output voltage is at the first level, or determining not to perform current compensation on the voltage buffer module when the second output voltage is at the second level.
  16. 16. The method of any of claims 9-12, wherein the voltage buffer is applied to a display driver chip, and the operating phase of the display driver chip includes an active display period, an inactive display period, and a vertical blanking period, and the misalignment calibration module operates in the inactive display period or the vertical blanking period.
  17. 17. A display driver chip comprising the voltage buffer of any of claims 1-8.
  18. 18. An electronic device comprising the voltage buffer of any of claims 1-8.

Description

Voltage buffer, voltage buffering method, display driving chip and electronic equipment Technical Field The present application relates to the field of display technologies, and in particular, to a voltage buffer, a voltage buffering method, a display driving chip, and an electronic device. Background In the field of display technology, the display quality of a display panel depends on the accuracy of the output voltage of a display driving chip, which is generated by a voltage buffer in the display driving chip. Therefore, it is desirable to provide a voltage buffer capable of improving the accuracy and stability of the output voltage of the display driving chip. Disclosure of Invention The application provides a voltage buffer, a voltage buffering method, a display driving chip and electronic equipment, which are used for improving the accuracy and stability of the output voltage of the voltage buffer in a misalignment calibration mode. The technical proposal is as follows: In one aspect, a voltage buffer is provided, the voltage buffer comprising a voltage buffer module and an offset calibration module, the voltage buffer module comprising a first output stage and a second output stage; The voltage buffer module is used for outputting a first output voltage to a load through the first output stage in a non-calibration mode or outputting a second output voltage to the offset calibration module through the second output stage in a calibration mode; And the offset calibration module is used for performing current compensation on the voltage buffer module based on the second output voltage under the condition that the second output voltage is received so as to calibrate direct current offset of the voltage buffer module. In one possible implementation, the voltage buffer module further comprises an input stage; the voltage buffer module is further configured to receive an input voltage through the input stage and convert the input voltage into an intermediate voltage, where the intermediate voltage acts on the first output stage in the non-calibration mode to output a first output voltage to a load through the first output stage, or acts on the second output stage in the calibration mode to output a second output voltage to the offset calibration module through the second output stage. In a possible implementation, the input stage comprises a positive input terminal and a negative input terminal, the input voltage is received by the positive input terminal and the negative input terminal, wherein the positive input terminal is used for receiving an electric signal of input data, the negative input terminal is used for receiving the first output voltage in the non-calibration mode, and the negative input terminal is used for receiving the electric signal of the input data in the calibration mode. In one possible implementation, the voltage buffer is a first-stage voltage buffer of two voltage buffers connected in series, and when a second-stage voltage buffer of the two voltage buffers completes calibration, the first-stage voltage buffer enters the calibration mode, and the input voltage of the first-stage voltage buffer is the output voltage of the second-stage voltage buffer. In one possible implementation, the offset calibration module includes a logic control circuit and a current compensation circuit; The logic control circuit is used for determining whether to perform current compensation on the voltage buffer module based on the second output voltage, and sending a first signal to the current compensation circuit under the condition that the current compensation on the voltage buffer module is determined; The current compensation circuit is used for inputting compensation current to the voltage buffer module under the condition that the first signal sent by the logic control circuit is received. In one possible implementation manner, the current compensation circuit includes N parallel current sources, where N is a positive integer greater than 1, the N current sources are connected to a first node through N first switches, one current source corresponds to one first switch, and the N first switches are used to adjust the magnitude of the compensation current; The first node is connected with one end of a current mirror in the voltage buffer module through a second switch, the first node is connected with the other end of the current mirror through a third switch, and the second switch and the third switch are used for adjusting the input position of the compensation current. In one possible implementation manner, the second output voltage is a first level when the voltage buffer module has a dc offset, and is a second level when the voltage buffer module has no dc offset; the logic control circuit is configured to determine to perform current compensation on the voltage buffer module when the second output voltage is at the first level, and determine not to perform current compensation on the voltage