Touch controllers, demodulation methods and touch systems

A demodulation method for use in a touch controller of a touch system, wherein the touch controller includes a signal generating module and a demodulating module, and the demodulation method comprises:

• during a pre-processing stage, using the signal generating module to output a first transmitting signal to a first transmit electrode of a plurality of transmit electrodes of a touch panel and not output any signal to the plurality of the transmit electrodes except the first transmit electrode at a first time;
• using the demodulating module to receive a first receiving signal at a receive electrode of a plurality of receive electrodes of the touch panel at the first time and generate a first component and a second component corresponding to the first receiving signal, wherein the first component and the second component relate to a phase between the first transmitting signal and the first receiving signal;
• using the signal generating module to output a second transmitting signal to a second transmit electrode of the plurality of transmit electrodes and not output any signal to the plurality of the transmit electrodes except the second transmit electrode at a second time;
• and
• using the demodulating module to receive a second receiving signal at the receive electrode at the second time, and generate a third component and a fourth component corresponding to the second receiving signal, wherein the third component and the fourth component relate to a phase between the second transmitting signal and the second receiving signal.

A touch system, comprising:

• a touch panel, comprising:
• a plurality of transmit electrodes;
• and
• a plurality of receive electrodes;
• and
• a touch controller, wherein the touch controller comprises:
• a signal generating module, coupled to a plurality of transmit electrodes of a touch panel, and configured to output a first transmitting signal to a first transmit electrode of the plurality of transmit electrodes and a second transmitting signal to a second transmit electrode of the plurality of transmit electrodes;
• and
• a demodulating module, coupled to a plurality of receive electrodes of the touch panel, and configured to receive a receiving signal at a receive electrode of the plurality of receive electrodes;
• wherein during a pre-processing stage:
• the signal generating module outputs the first transmitting signal to the first transmit electrodes and not outputs any signal to the plurality of the transmit electrodes except the first transmit electrode at a first time, and the demodulating module receives a first receiving signal at the receive electrode of the plurality of receive electrodes at the first time and generates a first component and a second component corresponding to the first receiving signal, wherein the first component and the second component relate to a phase between the first transmitting signal and the first receiving signal;
• the signal generating module outputs the second transmitting signal to the second transmit electrode and not outputs any signal to the plurality of the transmit electrodes except the second transmit electrode at a second time, and the demodulating module receives a second receiving signal at the receive electrode at the second time and generates a third component and a fourth component corresponding to the second receiving signal, wherein the third component and the fourth component relate to a phase between the second transmitting signal and the second receiving signal.