Continuous time correlator architecture

A method comprising:

• outputting a first signal to a first end of a capacitance to be measured;
• receiving a second signal from a second end of the capacitance;
• correlating the first signal and the second signal;
• and
• generating an output signal based on the correlating of the first signal and the second signal,
• wherein the output signal is proportional to a capacitance value of the capacitance.

A method comprising:

• outputting a first signal to a first end of a capacitance of a touch screen, wherein a capacitance value of the capacitance is configured to vary in response to a conductive element being proximate to or in contact with the touch screen;
• receiving a second signal from a second end of the capacitance;
• correlating the first signal and the second signal;
• generating an output signal based on the correlating of the first signal and the second signal, wherein the output signal is proportional to the capacitance value of the capacitance;
• sampling the output signal to determine whether the capacitance value of the capacitance changed;
• and
• determining whether the conductive element was proximate to or in contact with the touch screen based on whether the capacitance value of the capacitance changed.