PIC18F2221-E/ML Microchip Technology, PIC18F2221-E/ML Datasheet - Page 243

• Manufacturer Part Number: PIC18F2221-E/ML
• Description: 4KB, Flash, 512bytes-RAM, 25I/O, 8-bit Family,nanoWatt 28 QFN 6x6mm TUBE
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2221-E/ML

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 25
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 10x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

21.0
The
comparators that can be configured in a variety of
ways. The inputs can be selected from the analog
inputs multiplexed with pins RA0 through RA5, as well
as the on-chip voltage reference (see Section 22.0
“Comparator Voltage Reference Module”). The digi-
tal outputs (normal or inverted) are available at the pin
level and can also be read through the control register.
REGISTER 21-1:
© 2009 Microchip Technology Inc.
analog
COMPARATOR MODULE
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2-0
comparator
CMCON: COMPARATOR CONTROL REGISTER
PIC18F2221/2321/4221/4321 FAMILY
C2OUT: Comparator 2 Output bit
When C2INV = 0:
1 = C2 V
0 = C2 V
When C2INV = 1:
1 = C2 V
0 = C2 V
C1OUT: Comparator 1 Output bit
When C1INV = 0:
1 = C1 V
0 = C1 V
When C1INV = 1:
1 = C1 V
0 = C1 V
C2INV: Comparator 2 Output Inversion bit
1 = C2 output inverted
0 = C2 output not inverted
C1INV: Comparator 1 Output Inversion bit
1 = C1 output inverted
0 = C1 output not inverted
CIS: Comparator Input Switch bit
When CM<2:0> = 110:
1 = C1 V
0 = C1 V
CM<2:0>: Comparator Mode bits
Figure 21-1 shows the Comparator modes and the CM<2:0> bit settings.
bit 7
Legend:
R = Readable bit
-n = Value at POR
C2OUT
R-0
C2 V
C2 V
module
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
+ > C2 V
+ < C2 V
+ < C2 V
+ > C2 V
+ > C1 V
+ < C1 V
+ < C1 V
+ > C1 V
- connects to RA3/AN3/V
- connects to RA2/AN2/V
- connects to RA0/AN0
- connects to RA1/AN1
C1OUT
R-0
contains
IN
IN
IN
IN
IN
IN
IN
IN
-
-
-
-
-
-
-
-
C2INV
R/W-0
two
W = Writable bit
‘1’ = Bit is set
REF
REF
C1INV
R/W-0
The CMCON register (Register 21-1) selects the
comparator input and output configuration. Block
diagrams of the various comparator configurations are
shown in Figure 21-1.
+
-/CV
REF
R/W-0
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
CIS
R/W-1
CM2
x = Bit is unknown
R/W-1
CM1
DS39689F-page 243
R/W-1
CM0
bit 0