PIC16F688
FIGURE 7-5:
COMPARATOR I/O OPERATING MODES
Comparators Reset (POR Default Value)
CM<2:0> = 000
Two Independent Comparators
CM<2:0> = 100
A
VIN-
A
VIN-
C1IN-
C1IN-
(1)
Off
Off
C1
C2
C1OUT
C2OUT
C1
C2
VIN+
A
VIN+
A
C1IN+
C1IN+
A
VIN-
A
A
VIN-
C2IN-
C2IN-
C2IN+
(1)
VIN+
A
VIN+
C2IN+
Three Inputs Multiplexed to Two Comparators
CM<2:0> = 001
One Independent Comparator
CM<2:0> = 101
I/O
A
C1IN-
VIN-
C1IN-
CIS = 0 VIN-
(1)
Off
C1
VIN+
I/O
A
CIS = 1
C1IN+
C1IN+
C1OUT
C2OUT
C1
C2
VIN+
A
A
VIN-
A
A
VIN-
C2IN-
C2IN+
C2IN-
C2IN+
C2OUT
C2
VIN+
VIN+
Four Inputs Multiplexed to Two Comparators
CM<2:0> = 010
Two Common Reference Comparators with Outputs
CM<2:0> = 110
A
A
VIN-
C1IN-
C1IN-
CIS = 0
CIS = 1
VIN-
C1OUT
C2OUT
C1
C2
VIN+
A
C1IN+
C1OUT
C2OUT
C1
C2
VIN+
D
C1OUT(pin)
A
A
C2IN-
C2IN+
VIN-
CIS = 0
CIS = 1
A
A
VIN-
C2IN-
C2IN+
VIN+
VIN+
D
C2OUT(pin)
From CVREF Module
Two Common Reference Comparators
CM<2:0> = 011
Comparators Off (Lowest Power)
CM<2:0> = 111
A
VIN-
I/O
VIN-
C1IN-
C1IN-
C1OUT
(1)
C1
C2
VIN+
I/O
Off
C1
VIN+
I/O
C1IN+
C1IN+
A
A
VIN-
I/O
I/O
VIN-
C2IN-
C2IN+
C2IN-
C2IN+
(1)
C2OUT
Off
C2
VIN+
VIN+
Legend: A = Analog Input, ports always reads ‘0’
CIS = Comparator Input Switch (CMCON0<3>)
D = Comparator Digital Output
I/O = Normal port I/O
Note 1: Reads as ‘0’, unless CxINV = 1.
© 2007 Microchip Technology Inc.
DS41203D-page 57
MICROCHIP [ MICROCHIP ]
