PIC18F24J11 MICROCHIP [Microchip Technology], PIC18F24J11 Datasheet - Page 370

• Manufacturer Part Number: PIC18F24J11
• Description: 28/44-Pin, Low-Power, High-Performance USB Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F46J11 FAMILY
23.1
The comparator voltage reference module is controlled
through the CVRCON register
comparator voltage reference provides two ranges of
output voltage, each with 16 distinct levels. The range
to be used is selected by the CVRR bit (CVRCON<5>).
The primary difference between the ranges is the size
of the steps selected by the CV
(CVR<3:0>), with one range offering finer resolution.
The equations used to calculate the output of the
comparator voltage reference are as follows:
EQUATION 23-1:
REGISTER 23-1:
DS39932D-page 370
When CVRR = 1 and CVRSS = 0:
CV
When CVRR = 0 and CVRSS = 0:
CV
When CVRR = 1 and CVRSS = 1:
CV
When CVRR = 0 and CVRSS = 1:
CV
– V
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7
bit 6
bit 5
bit 4
bit 3-0
Note 1:
REF
REF
REF
REF
REF
CVREN
R/W-0
= ((CVR<3:0>)/24) x (AV
= ((AV
= ((CVR<3:0>)/24) x ((V
= (((V
-)
Configuring the Comparator
Voltage Reference
CVROE overrides the TRIS bit setting.
REF
DD
- AV
+) – V
CVREN: Comparator Voltage Reference Enable bit
1 = CV
0 = CV
CVROE: Comparator V
1 = CV
0 = CV
CVRR: Comparator V
1 = 0 to 0.667 CV
0 = 0.25 CV
CVRSS: Comparator V
1 = Comparator reference source, CV
0 = Comparator reference source, CV
CVR<3:0>: Comparator V
When CVRR = 1:
CV
When CVRR = 0:
CV
CVROE
REF
REF
SS
R/W-0
REF
)/4) + ((CVR<3:0>)/32) x (AV
CALCULATING OUTPUT
OF THE COMPARATOR
VOLTAGE REFERENCE
CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER
(BANKED F53h)
= ((CVR<3:0>)/24)  (CV
= (CV
REF
REF
REF
REF
-)/4) + ((CVR<3:0>)/32) x ((V
(1)
REF
circuit powered on
circuit powered down
voltage level is also output on the RA2/AN2/V
voltage is disconnected from the RA2/AN2/V
DD
RSRC
RSRC
+) – V
W = Writable bit
‘1’ = Bit is set
- AV
(Register
R/W-0
CVRR
/4) + ((CVR<3:0>)/32)  (CV
RSRC
to 0.75 CV
SS
REF
REF
)
REF
-)
REF
REF
, with CV
Selection bits
Range Selection bit
REF
Source Selection bit
Output Enable bit
23-1). The
RSRC
DD
Value Selection bits (0  (CVR<3:0>)  15)
CVRSS
RSRC
RSRC
- AV
R/W-0
REF
, with CV
SS
+)
)
/24 step size (low range)
)
RSRC
RSRC
RSRC
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
= (V
= AV
(1)
RSRC
R/W-0
CVR3
The comparator reference supply voltage can come
from either V
V
voltage source is selected by the CVRSS bit
(CVRCON<4>).
The settling time of the comparator voltage reference
must be considered when changing the CV
output (see
Characteristics”).
/32 step size (high range)
REF
DD
REF
)
+) – (V
– AV
- that are multiplexed with RA2 and RA3. The
REF
SS
REF
REF
-/CV
-/CV
Table 29-4
DD
-)
R/W-0
CVR2
REF
and V
REF
/C2INB pin
/C2INB pin
SS
 2011 Microchip Technology Inc.
in
x = Bit is unknown
, or the external V
Section 29.0 “Electrical
R/W-0
CVR1
R/W-0
CVR0
REF
+ and
bit 0
REF