PIC16F916-I/SP Microchip Technology, PIC16F916-I/SP Datasheet - Page 183

• Manufacturer Part Number: PIC16F916-I/SP
• Description: IC PIC MCU FLASH 8KX14 28SDIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F916-I/SP

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 28-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 24
• Eeprom Size: 256 x 8
• Ram Size: 352 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 352 B
• Interface Type: SSP/I2C/AUSART/SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 3
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DV164120
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

FIGURE 15-5:
A PWM output (Figure 15-6) has a time base (period)
and a time that the output stays high (duty cycle). The
frequency of the PWM is the inverse of the period
(1/period).
FIGURE 15-6:
15.3.1
The PWM period is specified by writing to the PR2
register. The PWM period can be calculated using the
following formula:
PWM frequency is defined as 1/[PWM period].
 2004 Microchip Technology Inc.
(TMR2 prescale value)
Note 1:
CCPR1H (Slave)
PWM period = (PR2) + 1] • 4 • T
Comparator
CCPR1L
TMR2 = PR2
Duty Cycle Registers
TMR2
PR2
Comparator
Duty Cycle
PWM PERIOD
The 8-bit timer is concatenated with 2-bit internal Q
clock, or 2 bits of the prescaler, to create 10-bit time
base.
Period
(1)
TMR2 = Duty Cycle
Clear Timer,
CCP1 pin and
latch D.C.
SIMPLIFIED PWM BLOCK
DIAGRAM
PWM OUTPUT
TMR2 = PR2
CCP1CON<5:4>
R
S
OSC
Q
•
TRISC<2>
CCP1/SEG10
RC5/T1CKI/
Preliminary
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
• TMR2 is cleared
• The RC5/T1CKI/CCP1/SEG10 pin is set
• The PWM duty cycle is latched from CCPR1L into
15.3.2
The PWM duty cycle is specified by writing to the
CCPR1L register and to the CCP1CON<5:4> bits. Up
to 10-bit resolution is available. The CCPR1L contains
the eight MSbs and the CCP1CON<5:4> contains the
two LSbs. This 10-bit value is represented by
CCPR1L:CCP1CON<5:4>. The following equation is
used to calculate the PWM duty cycle in time:
CCPR1L and CCP1CON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPR1H until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPR1H is a read-only register.
The CCPR1H register and a 2-bit internal latch are
used to double buffer the PWM duty cycle. This double
buffering is essential for glitch-free PWM operation.
When the CCPR1H and 2-bit latch match TMR2, con-
catenated 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 formula:
PWM Resolution
T
(exception: if PWM duty cycle = 0%, the
RC5/T1CKI/CCP1/SEG10 pin will not be set)
CCPR1H
Note:
Note:
OSC
PWM duty cycle =(CCPR1L:CCP1CON<5:4>) •
• (TMR2 prescale value)
The Timer2 postscaler (see Section 7.0
“Timer2 Module”) is not used in the
determination of the PWM frequency. The
postscaler could be used to have a servo
update rate at a different frequency than
the PWM output.
PWM DUTY CYCLE
If the PWM duty cycle value is longer than
the
RC5/T1CKI/CCP1/SEG10 pin will not be
cleared.
=
log
--------------------------------------------------------------------------- bits
PWM


-------------------------------------------------------------
F
PIC16F91X
PWM
log
TMR2 Prescaler
F
OSC
2
DS41250B-page 181
period,


the