PIC16F1847_13 Datasheet, PDF (317/440 Pages) Microchip Technology – 18/20/28-Pin Flash Microcontrollers with XLP Technology

PIC16(L)F1847
27.0 CAPACITIVE SENSING
MODULE
The Capacitive Sensing (CPS) module allows for an
interaction with an end user without a mechanical
interface. In a typical application, the CPS module is
attached to a pad on a Printed Circuit Board (PCB),
which is electrically isolated from the end user. When the
end user places their finger over the PCB pad, a
capacitive load is added, causing a frequency shift in the
CPS module. The CPS module requires software and at
least one timer resource to determine the change in
frequency. Key features of this module include:
• Analog MUX for monitoring multiple inputs
• Capacitive sensing oscillator
• Multiple Power modes
• High power range with variable voltage references
• Multiple timer resources
• Software control
• Operation during Sleep
FIGURE 27-1:
CAPACITIVE SENSING BLOCK DIAGRAM
CPS0
CPS1
CPS2
CPS3
CPS4
CPS5
CPS6
CPS7
CPS8
CPS9
CPS10
CPS11
T0XCS
CPSCH<3:0>
CPSON⁽¹⁾
T0CKI
0
1
CPSRNG<1:0>
CPSON
Capacitive
Sensing
Oscillator
CPSOSC
0
Int.
Ref-
Ref.
1 _DAC
0
Ref+
1 FVR
CPSCLK
CPSOUT
CPSRM
Timer0 Module
TMR0CS
Set
TMR0IF
FOSC/4 0
1
TMR0
Overflow
T1CS<1:0>
FOSC
FOSC/4
T1OSC/
T1CKI
T1GSEL<1:0>
T1G
sync_C1OUT
sync_C2OUT
Timer1 Module
TMR1H:TMR1L
EN
Timer1 Gate
Control Logic
Note 1: If CPSON = 0, disabling capacitive sensing, no channel is selected.
 2011-2013 Microchip Technology Inc.
Preliminary
DS40001453D-page 317