PIC18F4580-E/PT Microchip Technology, PIC18F4580-E/PT Datasheet - Page 174

• Manufacturer Part Number: PIC18F4580-E/PT
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,TQFP,44PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F4580-E/PT

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: CAN, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 36
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 1.5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC18F2480/2580/4480/4580
The CCPR1H 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 CCPR1H and 2-bit latch match TMR2,
concatenated with an internal 2-bit Q clock or 2 bits of
the TMR2 prescaler, the CCP1 pin is cleared.
The maximum PWM resolution (bits) for a given PWM
frequency is given by the equation.
TABLE 16-4:
16.4.3
The PWM auto-shutdown features of the Enhanced
CCP
PIC18F4480/4580 (40/44-pin) devices. The operation
of this feature is discussed in detail in Section 17.4.7
“Enhanced PWM Auto-Shutdown”.
Auto-shutdown features are not available for CCP1.
DS39637D-page 174
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
PWM Frequency
module
PWM AUTO-SHUTDOWN
(ECCP1 ONLY)
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
are
available
2.44 kHz
to
FFh
16
10
ECCP1
9.77 kHz
FFh
10
in
4
39.06 kHz
EQUATION 16-3:
16.4.4
The following steps should be taken when configuring
the CCP module for PWM operation:
1.
2.
3.
4.
5.
Note:
FFh
10
1
Set the PWM period by writing to the PR2
register.
Set the PWM duty cycle by writing to the
CCPR1L register and CCP1CON<5:4> bits.
Make the CCP1 pin an output by clearing the
appropriate TRIS bit.
Set the TMR2 prescale value, then enable
Timer2 by writing to T2CON.
Configure the CCP1 module for PWM operation.
PWM Resolution (max) =
If the PWM duty cycle value is longer than
the PWM period, the CCP1 pin will not be
cleared.
SETUP FOR PWM OPERATION
156.25 kHz
3Fh
1
8
© 2009 Microchip Technology Inc.
312.50 kHz
log
1Fh
1
7
log(2)
⎛
⎝
F
F
PWM
OSC
⎞
⎠
416.67 kHz
bits
6.58
17h
1