PIC18F8390T-I/PT Microchip Technology, PIC18F8390T-I/PT Datasheet - Page 156

• Manufacturer Part Number: PIC18F8390T-I/PT
• Description: IC PIC MCU FLASH 4KX16 80TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F8390T-I/PT

• 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: 8KB (4K x 16)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• Processor Series: PIC18F
• 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: 4.2 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
• For Use With: XLT80PT3 - SOCKET TRAN ICE 80MQFP/TQFPDM163028 - BOARD DEMO PICDEM LCDAC164320 - MODULE SKT MPLAB PM3 80TQFPAC174011 - MODULE SKT PROMATEII 80TQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

PIC18F6390/6490/8390/8490
14.4.2
The PWM duty cycle is specified by writing to the
CCPR2L register and to the CCP2CON<5:4> bits. Up
to 10-bit resolution is available. The CCPR2L contains
the eight MSbs and the CCP2CON<5:4> bits contain
the two LSbs. This 10-bit value is represented by
CCPR2L:CCP2CON<5:4>. The following equation is
used to calculate the PWM duty cycle in time:
EQUATION 14-2:
CCPR2L and CCP2CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR2H until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPR2H is a read-only register.
TABLE 14-4:
DS39629C-page 154
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
PWM Duty Cycle = (CCPR2L:CCP2CON<5:4>) •
PWM Frequency
PWM DUTY CYCLE
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
T
OSC
• (TMR2 Prescale Value)
2.44 kHz
FFh
16
14
9.77 kHz
FFh
12
4
39.06 kHz
The CCPR2H register and a 2-bit internal latch are
used to double-buffer the PWM duty cycle. This
double-buffering is essential for glitchless PWM
operation.
When the CCPR2H and 2-bit latch match TMR2,
concatenated with an internal 2-bit Q clock or 2 bits of
the TMR2 prescaler, the CCP2 pin is cleared.
The maximum PWM resolution (bits) for a given PWM
frequency is given by the equation:
EQUATION 14-3:
Note:
FFh
10
1
PWM Resolution (max)
If the PWM duty cycle value is longer than
the PWM period, the CCP2 pin will not be
cleared.
156.25 kHz
3Fh
1
8
© 2007 Microchip Technology Inc.
312.50 kHz
=
1Fh
log
-----------------------------bits
1
7
log
⎛
⎝
---------------
F
F
PWM
2 ( )
OSC
416.67 kHz
⎞
⎠
6.58
17h
1