PIC18F1230 MICROCHIP [Microchip Technology], PIC18F1230 Datasheet - Page 180

• Manufacturer Part Number: PIC18F1230
• Description: 18/20/28-Pin, Enhanced Flash Microcontrollers with nanoWatt Technology, High-Performance PWM and A/D
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F1230/1330
FIGURE 17-1:
17.2
The full range of voltage reference cannot be realized
due to the construction of the module. The transistors
on the top and bottom of the resistor ladder network
(Figure 17-1) keep CV
reference source rails. The voltage reference is derived
from the reference source; therefore, the CV
changes with fluctuations in that source. The tested
absolute accuracy of the voltage reference can be
found in Section 22.0 “Electrical Characteristics”.
TABLE 17-1:
DS39758B-page 178
CVRCON
CMCON
Legend: Shaded cells are not used with the comparator voltage reference.
Name
Voltage Reference Accuracy/Error
CVREN
C2OUT
Bit 7
REGISTERS ASSOCIATED WITH COMPARATOR VOLTAGE REFERENCE
V
AV
CVREN
CVRR
REF
DD
COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
+
REF
C1OUT
CVRSS = 1
CVRSS = 0
Bit 6
from approaching the
—
AV
SS
C0OUT
CVRR
CVRSS = x
Bit 5
16 Steps
REF
Advance Information
output
CVRSS
8R
Bit 4
—
R
R
R
R
R
R
R
CVR3
Bit 3
17.3
When the device wakes up from Sleep through an
interrupt or a Watchdog Timer time-out, the contents of
the CVRCON register are not affected. To minimize
current consumption in Sleep mode, the voltage
reference should be disabled.
17.4
A device Reset disables the voltage reference by clearing
bit, CVREN (CVRCON<7>). This Reset selects the high-
voltage range by clearing bit, CVRR (CVRCON<5>). The
CVR value select bits are also cleared.
—
8R
Operation During Sleep
Effects of a Reset
CMEN2
CVR2
CVR3:CVR0
Bit 2
CMEN1
CVR1
Bit 1
© 2006 Microchip Technology Inc.
CV
CMEN0
REF
CVR0
Bit 0
on page
Values
Reset
42
42