PIC18LF8490-I/PT Microchip Technology, PIC18LF8490-I/PT Datasheet - Page 264

• Manufacturer Part Number: PIC18LF8490-I/PT
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,TQFP,80PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18LF8490-I/PT

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, LCD, POR, PWM, WDT
• Number Of I /o: 66
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• Processor Series: PIC18LF
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 768 B
• Interface Type: SPI, I2C, EUSART, AUSART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 66
• Number Of Timers: 1 x 8
• Operating Supply Voltage: 2 V to 5.5 V
• 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, DM163028
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

PIC18F6390/6490/8390/8490
22.2
The LCD driver module has 3 possible clock sources:
• (F
• T13CKI Clock/32
• INTRC/32
The first clock source is the system clock divided by
8192 ((F
provide about 1 kHz output when the system clock is
8 MHz. The divider is not programmable. Instead, the
LCD prescaler bits, LCDPS<3:0>, are used to set the
LCD frame clock rate.
The second clock source is the Timer1 oscillator/32.
This also gives about 1 kHz when a 32.768 kHz crystal
is used with the Timer1 oscillator. To use the Timer1
oscillator
(T1CON<3>) bit should be set.
FIGURE 22-2:
DS39629C-page 262
OSC
Crystal Oscillator
/4)/8192
System Clock
Nom F
OSC
TMR1 32 kHz
Internal RC Oscillator
LCD Clock Source Selection
(F
as
/4)/8192). This divider ratio is chosen to
OSC
RC
a
/4)
= 31.25 kHz
clock
LCD CLOCK GENERATION
source,
÷8192
÷32
÷32
(LCDCON<3:2>)
the
CS1:CS0
T1OSCEN
÷4
÷2
(LCDCON<1:0>)
LMUX1:LMUX0
QUAD
STAT
TRIP
DUP
The third clock source is a 31.25 kHz internal RC
oscillator/32, which provides approximately 1 kHz
output.
The second and third clock sources may be used to
continue running the LCD while the processor is in
Sleep.
Using the bits, CS1:CS0 (LCDCON<3:2>), any of these
clock sources can be selected.
22.2.1
A 16-bit counter is available as a prescaler for the LCD
clock. The prescaler is not directly readable or writable;
its value is set by the LP3:LP0 bits (LCDPS<3:0>), which
determine the prescaler assignment and prescale ratio.
The prescale values from 1:1 through 1:32768 in
power-of-2 increments are selectable.
4-Bit Prog Prescaler
LCD PRESCALER
(LCDPS<3:0>)
LP3:LP0
© 2007 Microchip Technology Inc.
(LCDCON<1:0>)
LMUX1:LMUX0
Ring Counter
÷1, 2, 3, 4