PIC18F6621-I/PT Microchip Technology, PIC18F6621-I/PT Datasheet - Page 252

• Manufacturer Part Number: PIC18F6621-I/PT
• Description: IC PIC MCU FLASH 32KX16 64TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F6621-I/PT

• Core Size: 8-Bit
• Program Memory Size: 64KB (32K x 16)
• Core Processor: PIC
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 3.75K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TFQFP
• Controller Family/series: PIC18
• No. Of I/o's: 53
• Eeprom Memory Size: 1024Byte
• Ram Memory Size: 3.75KB
• Cpu Speed: 40MHz
• No. Of Timers: 5
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3840 B
• Interface Type: MSSP, SPI, I2C, EUSART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 53
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DV164136, DM183032
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 12 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT64PT5 - SOCKET TRAN ICE 64MQFP/TQFPAC164319 - MODULE SKT MPLAB PM3 64TQFPDV007003 - PROGRAMMER UNIVERSAL PROMATE II
• Lead Free Status / Rohs Status: Details

PIC18F6525/6621/8525/8621
FIGURE 22-1:
22.2
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 22-1) keep CV
ence 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 27.0 “Electrical Characteristics”.
22.3
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.
DS39612B-page 250
CVREN
Note: R is defined in Section 27.0 “Electrical Characteristics”.
Voltage Reference Accuracy/Error
Operation During Sleep
CVRSS = 0
CV
REF
AV
REF
COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
DD
from approaching the refer-
V
CVRSS = 1
REF
8R
+
R
REF
output
R
16 Stages
16-1 Analog Mux
22.4
A device Reset disables the voltage reference by
clearing bit CVREN (CVRCON<7>). This Reset also
disconnects the reference from the RA2 pin by clearing
bit CVROE (CVRCON<6>) and selects the high-
voltage range by clearing bit CVRR (CVRCON<5>).
The VRSS value select bits, CVRCON<3:0>, are also
cleared.
22.5
The voltage reference module operates independently
of the comparator module. The output of the reference
generator may be connected to the RF5 pin if the
TRISF<5> bit is set and the CVROE bit is set. Enabling
the voltage reference output onto the RF5 pin
configured as a digital input will increase current
consumption. Connecting RF5 as a digital output with
VRSS enabled will also increase current consumption.
The RF5 pin can be used as a simple D/A output with
limited drive capability. Due to the limited current drive
capability, a buffer must be used on the voltage
reference output for external connections to V
Figure 22-2 shows an example buffering technique.
R
Effects of a Reset
Connection Considerations
R
 2005 Microchip Technology Inc.
8R
CVR3
CVR0
(From CVRCON<3:0>)
CVRR
CVRSS = 0
CVRSS = 1
V
REF
-
REF
.