FIELD

The present disclosure relates to the technical field of semiconductors, and in particular to a touch display control circuit, a control method and an electronic device.

BACKGROUND

With the development of the technology, an electronic device including a liquid-crystal display (LCD) screen with a touch function is increasingly popular. Nowadays, capacitive touch technology is widely used in thin-film-transistor liquid crystal display (TFT-LCD) screen.

Luminance and dynamic response speeds of a super twisted nematic liquid crystal display (STN-LCD) screen, a twisted nematic liquid crystal display (TN-LCD) screen and a color super twisted nematic liquid crystal display (CSTN-LCD) screen are lower than that of the TFT-LCD screen. However, the STN-LCD screen and the like is still widely used in electronic devices due to a low cost. If a touch screen is attached with such liquid crystal display screen with the low cost, the integrated liquid-crystal display screen has poor display effect and a high cost. Therefore, the STN-LCD screen and the like are only used to display and cannot achieve the touch function.

Based on the above, a technical problem to be solved by those skilled in the art is to provide a touch display circuit, such that the STN-LCD screen, the TN-LCD screen and the CSTN-LCD screen can achieve the touch function without changing their original configurations.

SUMMARY

In view of this, a touch display control circuit, a control method, and an electronic device are provided in the present disclosure, such that the STN-LCD screen, the TN-LCD screen and the CSTN-LCD screen can achieve the touch function without changing their original configurations.

Based on the above, the following technical solutions are provided in the present disclosure.

A touch display control circuit for driving a liquid crystal display screen is provided. The touch display control circuit includes a display driving circuit and a touch detection circuit. The display driving circuit includes a signal transmission line, a signal selection circuit and a reference voltage generation circuit. The signal transmission line is configured to transmit a gate signal and a common signal. The signal selection circuit is configured to select a preset control voltage based on display control timing or touch control timing. The reference voltage generation circuit is connected to the signal selection circuit and is configured to provide the preset control voltage. The touch detection circuit is connected to the signal selection circuit and is configured to perform touch detection based on the touch control timing.

In an embodiment, the signal selection circuit includes a gate signal selection sub-circuit and a common electrode signal selection sub-circuit. The gate signal selection sub-circuit is connected to the reference voltage generation circuit, and is configured to select a target gate voltage based on the display control timing and transmit the target gate voltage to a gate line in the signal transmission line. The common electrode signal selection sub-circuit is connected to the reference voltage generation circuit, and is configured to select a target common voltage based on the display control timing or the touch control timing, and transmit the target common voltage to a common line in the signal transmission line.

In an embodiment, the number of the touch detection circuit is equal to or greater than two. Each common line is connected to one common electrode signal selection sub-circuit. Each common electrode signal selection sub-circuit is connected to any one of the touch detection circuits.

In an embodiment, each common line is connected to one common electrode signal selection sub-circuit. Multiple common electrode signal selection sub-circuits are connected to a same touch detection circuit.

In an embodiment, the signal selection circuit includes multiple switches. A control terminal of each of the multiple switches is controlled based on the display control timing or touch control timing, to select the preset control voltage and transmit the selected preset control voltage to the signal transmission line.

In an embodiment, the number of the touch detection circuit is equal to or greater than two. Each common line is connected to one signal selection circuit. Each signal selection circuit is connected to any one of the touch detection circuit.

In an embodiment, each common line is connected to one signal selection circuit. Multiple signal selection circuits are connected to a same touch detection circuit.

In an embodiment, the touch detection circuit includes an amplifier and multiple switches. The amplifier is configured to detect a change value of self-capacitance of a common electrode and output a voltage signal corresponding to the change value of the self-capacitance.

A control method applied to the touch display control circuit is provided. The control method includes: controlling, based on the display control timing, the display driving circuit to be in an on-state and the touch detection circuit to be in an off-state, and selecting the preset control voltage, to allow the display driving circuit to output the preset control voltage to the signal transmission line, during a period of display timing; and controlling, based on the touch control timing, the touch detection circuit to perform touch detection, during a period of display touch timing.

In an embodiment, the period of display touch timing includes a first sub-period and a second sub-period. During the first sub-period, the display driving circuit is in the on-state, and the touch detection circuit is in the off-state and a self-correction state. During the second sub-period, the touch detection circuit performs the touch detection.

In an embodiment, the method includes performing the display control timing and the touch control timing based on a predetermined rule. The predetermined rule includes that: m display control timing and n display touch control timing are performed alternately, where m is an integer greater than or equal to zero, and n is an integer greater than or equal to one.

An electronic device is provided, which includes a body and the above-described touch display control circuit.

Compared with the conventional technology, the technical solutions in the present disclosure have the following advantages. A touch display control circuit is provided in the present disclosure. The touch display control circuit is configured to drive the STN-LCD screen, the TN-LCD screen and the CSTN-LCD screen. The touch display control circuit includes a display driving circuit and a touch detection circuit. The display driving circuit includes a signal transmission line, multiple groups of signal selection circuits, and a reference voltage generation circuit. The signal transmission line is configured to transmit a gate signal and a common signal. The signal selection circuit is configured to select a preset control voltage based on display control timing or touch control timing. The reference voltage generation circuit is configured to provide the preset control voltage. The touch detection circuit is connected to the signal selection circuit and is configured to perform touch detection based on the display touch control timing. It is to be seen that with the touch display control circuit provided in the present disclosure, the STN-LCD screen, the TN-LCD screen and the CSTN-LCD screen can achieve the touch function without changing their original configurations.

