PIC18F65K90-I/MR Microchip Technology, PIC18F65K90-I/MR Datasheet - Page 397

• Manufacturer Part Number: PIC18F65K90-I/MR
• Description: 32kB Flash, 2kB RAM, 1kB EE, NanoWatt XLP, LCD 64 QFN 9x9x0.9mm TUBE
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F65K90-I/MR

• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 32 KB
• Data Ram Size: 2 KB
• Interface Type: I2C, SPI
• Maximum Clock Frequency: 64 MHz
• Number Of Timers: 8
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 125 C
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit, 16 Channel
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 64MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 53
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 16x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VFQFN Exposed Pad
• Lead Free Status / Rohs Status: Details

25.0
The comparator voltage reference is a 32-tap resistor
ladder network that provides a selectable reference
voltage. Although its primary purpose is to provide a
reference for the analog comparators, it may also be
used independently of them.
A block diagram of the module is shown in
The resistor ladder is segmented to provide a range of
CV
conserve power when the reference is not being used.
The module’s supply reference can be provided from
either device V
25.1
The comparator voltage reference module is controlled
through the CVRCON register
comparator voltage reference provides a range of
output voltage with 32 levels.
The CVR<4:0> selection bits (CVRCON<4:0>) offer a
range of output voltages.
comparator voltage reference is computed.
REGISTER 25-1:
 2009-2011 Microchip Technology Inc.
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 7
bit 6
bit 5
bit 4-0
REF
CVREN
R/W-0
values and has a power-down function to
COMPARATOR VOLTAGE
REFERENCE MODULE
Configuring the Comparator
Voltage Reference
DD
CVREN: Comparator Voltage Reference Enable bit
1 = CV
0 = CV
CVROE: Comparator V
1 = CV
0 = CV
CVRSS: Comparator V
1 = Comparator reference source: CV
0 = Comparator reference source: CV
CVR<4:0>: Comparator V
When CVRSS = 1 :
CV
When CVRSS = 0 :
CV
/V
CVROE
REF
REF
R/W-0
SS
or an external voltage reference.
CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER
= (V
= (AV
REF
REF
REF
REF
Equation 25-1
REF
circuit is powered on
circuit is powered down
voltage level is output on the CV
voltage level is disconnected from the CV
SS
W = Writable bit
‘1’ = Bit is set
-) + (CVR<4:0>/32)  (V
) + (CVR<4:0>/32)  (AV
CVRSS
(Register
R/W-0
REF
REF
shows how the
REF
Figure
Source Selection bit
Output Enable bit
25-1). The
Value Selection (0  CVR<4:0>  31) bits
R/W-0
CVR4
25-1.
RSRC
RSRC
REF
DD
+ – V
– AV
= V
= AV
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
REF
PIC18F87K90 FAMILY
REF
R/W-0
CVR3
REF
SS
EQUATION 25-1:
The comparator reference supply voltage can come
from either V
V
voltage source is selected by the CVRSS bit
(CVRCON<5>).
The settling time of the comparator voltage reference
must be considered when changing the CV
output (see
Characteristics”
pin
DD
REF
If CVRSS = 1 :
C
If CVRSS = 0 :
C
)
+ – V
-)
VREF
VREF
– AV
- that are multiplexed with RA3 and RA2. The
REF
REF
= (V
= (AV
SS
pin
-
REF
Table 31-2
DD
SS
R/W-0
CVR2
-) + (CVR<4:0>/32) • (V
) + (CVR<4:0>/32) • (AV
and V
).
SS
in
, or the external V
x = Bit is unknown
Section 31.0 “Electrical
R/W-0
CVR1
DS39957D-page 397
REF
DD
+ – V
– AV
R/W-0
CVR0
REF
REF
SS
+ and
bit 0
)
-)
REF