PIC16F913-E/SS Microchip Technology, PIC16F913-E/SS Datasheet - Page 218

• Manufacturer Part Number: PIC16F913-E/SS
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,SSOP,28PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F913-E/SS

• Rohs Compliant: YES
• 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
• Program Memory Size: 7KB (4K x 14)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 28-SSOP
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: SSP, I2C, AUSART, SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 2
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 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 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC16F913/914/916/917/946
15.3.1
The PWM period is specified by the PR2 register of
Timer2. The PWM period can be calculated using the
formula of Equation 15-1.
EQUATION 15-1:
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
• TMR2 is cleared
• The CCPx pin is set. (Exception: If the PWM duty
• The PWM duty cycle is latched from CCPRxL into
15.3.2
The PWM duty cycle is specified by writing a 10-bit value
to multiple registers: CCPRxL register and CCPx<1:0>
bits of the CCPxCON register. The CCPRxL contains
the eight MSbs and the CCPx<1:0> bits of the
CCPxCON register contain the two LSbs. CCPRxL and
CCPx<1:0> bits of the CCPxCON register can be written
to at any time. The duty cycle value is not latched into
CCPRxH until after the period completes (i.e., a match
between PR2 and TMR2 registers occurs). While using
the PWM, the CCPRxH register is read-only.
Equation 15-2 is used to calculate the PWM pulse
width.
Equation 15-3 is used to calculate the PWM duty cycle
ratio.
DS41250F-page 216
cycle = 0%, the pin will not be set.)
CCPRxH.
Note:
Note:
PWM Period
PWM PERIOD
The Timer2 postscaler (see Section 7.1
“Timer2 Operation”) is not used in the
determination of the PWM frequency.
PWM DUTY CYCLE
T
OSC
=
= 1/F
(TMR2 Prescale Value)
[
PWM PERIOD
(
PR2
OSC
)
+
1
] 4 T
•
•
OSC
•
EQUATION 15-2:
EQUATION 15-3:
The CCPRxH 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.
The 8-bit timer TMR2 register is concatenated with
either the 2-bit internal system clock (F
the prescaler, to create the 10-bit time base. The system
clock is used if the Timer2 prescaler is set to 1:1.
When the 10-bit time base matches the CCPRxH and
2-bit latch, then the CCPx pin is cleared (see
Figure 15-3).
Duty Cycle Ratio
Pulse Width
=
(
T
=
CCPRxL:CCPxCON<5:4>
OSC
PULSE WIDTH
DUTY CYCLE RATIO
(
---------------------------------------------------------------------- -
CCPRxL:CCPxCON<5:4>
© 2007 Microchip Technology Inc.
•
(TMR2 Prescale Value)
4 PR2
(
+
OSC
1
)
), or 2 bits of
)
•
)