17 Integrated Touch Controller (ITC)

The Integrated Touch Controller (ITC) allows measuring the capacitances of the capacitive sensors connected to CVDANx pins. The sensor’s capacitance is processed using a Capacitive Voltage Divider algorithm (CVD). The Integrated Touch Controller CVD procedure is available/predefined in hardware and can be programmed in software-defined Acquisition and Post-Processing/Math sequences.

The Integrated Touch Controller has the following features:

• Up to 32 CVD Records. Each Record can be Assigned to Any Analog Input.
• Up to Three CVD Lists. Each List:
  • Joins a group of the records.
  • Has a balance timer selection the same for all records in the list.
  • Has a processing trigger selection to scan (process) all list records.
  • Can compare the records' results with predefined thresholds (digital comparator).
  • Has a programmable data acquisition sequencer and a post-processing sequencer.
• Data Acquisition Sequencer:
  • Supports up to 16 steps/commands.
  • Controls charge/discharge processes for CVD algorithm implementation.
  • Controls CVD balance time and conversion.
  • Can drive high/low or tri-state the analog inputs and digital TX pins and CVD guards.
• Post-Processing (Math) Sequencer:
  • Supports up to 16 steps/commands.
  • Can add or subtract the conversion results.
  • Has several accumulators to store intermediate data.