7.1 Introduction
On selected devices, the PTC includes a feature to acquire four channels simultaneously in Mutual Capacitance mode. Minimum four simultaneous measurements are required to resolve each channel’s node measurement, combining analog and digital oversampling with the net effect of an overall improvement in SNR or a reduction in response time.
By using Boost mode, one of the following benefits can be achieved:
- Since a given node is measured four times, SNR improves by two (square root of oversample times). In a noisy system SNR is improved by two without compromising the response time.
- The response time can be reduced to 1/4 by reducing the analog oversamples to 1/4th to retain the same SNR. Example: The filter level can be reduced from 32 to 8 without compromising on SNR by enabling the Boost mode.
Supported devices:
- SAM L1x
- PIC32CM-LE
- ATtiny161x
- ATtiny321x
- AVR-DA