C8051F70X_0910 Datasheet, PDF (72/290 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F70x/71x
13. Capacitive Sense (CS0)
The Capacitive Sense subsystem uses a capacitance-to-digital circuit to determine the capacitance on a
port pin. The module can take measurements from different port pins using the module’s 32-channel ana-
log multiplexer. The module is enabled only when the CS0EN bit (CS0CN) is set to 1. Otherwise the mod-
ule is in a low-power shutdown state. The module can be configured to take measurements on one port pin
or a group of port pins, using auto-scan. An accumulator can be configured to accumulate multiple conver-
sions on an input channel. Interrupts can be generated when CS0 completes a conversion or when the
measured value crosses a threshold defined in CS0THH:L.
CS0CN
CS0CF
CS0SS CS0SE
Auto-Scan
Logic
CS0MX
16-Bit
Capacitor to Digital
000
Start
Conversion
001
010
011
100
101
110
111
CS0BUSY (W)
Timer 0 Overflow
Timer 2 Overflow
Timer 1 Overflow
Timer 3 Overflow
Reserved
Initiated continuously
Initiated continuously
when auto-scan
enabled
20-Bit Accumulator
...
Converter
CS0DH CS0DL
Greater Than
Compare Logic
CS0CMPF
CS0THH CS0THL
Figure 13.1. CS0 Block Diagram
72
Rev. 0.3