Waveform generation circuit for finely tunable sensing frequency

A method, comprising:

• storing a plurality of data samples for generating a capacitive sensing waveform in a memory;
• upon determining that a saturation limit has not been reached, accessing the memory using a sequence of memory addresses to generate a rising edge of the capacitive sensing waveform;
• upon determining that the saturation limit has been reached, repeatedly accessing the memory using a first memory address of the sequence of memory addresses to generate a flat-top portion of the capacitive sensing waveform;
• and
• performing capacitive sensing using the capacitive sensing waveform.

A waveform generator, comprising:

• circuitry configured to set a frequency of a capacitive sensing waveform by adjusting a number of clock cycles used to generate a half period of the capacitive sensing waveform;
• circuitry configured to set a rising edge and a flat-top portion of the half period of the capacitive sensing waveform by adjusting a phase increment value and a saturation limit value;
• and
• circuitry configured to generate addresses for accessing a memory that stores data samples for creating the half period of the capacitive sensing waveform based on the number of clock cycles, the phase increment value, and the saturation limit value.