PIC12F635-E/MD MICROCHIP [Microchip Technology], PIC12F635-E/MD Datasheet - Page 76

• Manufacturer Part Number: PIC12F635-E/MD
• Description: 8/14-Pin, Flash-Based 8-Bit CMOS Microcontrollers with nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC12F635/PIC16F636/639
7.3
There are eight modes of operation for the comparator.
The CM<2:0> bits of the CMCON0 register are used to
select these modes as shown in Figures 7-6 and 7-7.
I/O lines change as a function of the mode and are
designed as follows:
• Analog function (A): digital input buffer is disabled
• Digital function (D): comparator digital output,
• Normal port function (I/O): independent of
FIGURE 7-6:
DS41232D-page 74
Legend: A = Analog Input, ports always reads ‘0’
Note 1:
overrides port function
comparator
Comparator Reset (POR Default Value – low power)
CM<2:0> = 000
Comparator with Output
CM<2:0> = 001
Comparator without Output
CM<2:0> = 010
Comparator with Output and Internal Reference
CM<2:0> = 011
COUT (pin) D
COUT (pin) I/O
COUT (pin)
COUT (pin) D
CIN-
CIN+
Comparator Configuration
CIN-
CIN+
I/O = Normal port I/O
Reads as ‘0’, unless CINV = 1.
CIN-
CIN+
CIN-
CIN+
A
A
A
A
A
I/O
A
A
I/O
COMPARATOR I/O OPERATING MODES (PIC12F635)
From CV
REF
Off
COUT
Module
(1)
COUT
COUT
Comparator w/o Output and with Internal Reference
CM<2:0> = 100
CM<2:0> = 101
CM<2:0> = 110
Comparator Off (Lowest power)
CM<2:0> = 111
Multiplexed Input with Internal Reference and Output
Multiplexed Input with Internal Reference
CIS = Comparator Input Switch (CMCON0<3>)
D = Comparator Digital Output
COUT (pin) I/O
The port pins denoted as “A” will read as a ‘0’
regardless of the state of the I/O pin or the I/O control
TRIS bit. Pins used as analog inputs should also have
the corresponding TRIS bit set to ‘1’ to disable the
digital output driver. Pins denoted as “D” should have
the corresponding TRIS bit set to ‘0’ to enable the
digital output driver.
COUT (pin) D
COUT (pin)
Note:
COUT (pin) I/O
CIN-
CIN+
CIN-
CIN+
CIN-
CIN+
CIN-
CIN+
I/O
I/O
A
A
A
A
I/O
Comparator interrupts should be disabled
during a Comparator mode change to
prevent unintended interrupts.
A
I/O
CIS = 0
CIS = 1
CIS = 0
CIS = 1
© 2007 Microchip Technology Inc.
From CV
From CV
From CV
REF
REF
Off
REF
Module
(1)
Module
Module
COUT
COUT
COUT