PIC16F1937-I/P Microchip Technology, PIC16F1937-I/P Datasheet - Page 194

• Manufacturer Part Number: PIC16F1937-I/P
• Description: IC PIC MCU FLASH 512KX14 40-PDIP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F1937-I/P

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 40-DIP (0.600", 15.24mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 32MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 36
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 14x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: EUSART/MI2C/SPI
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 36
• Number Of Timers: 5
• 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
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 14-ch x 10-bit
• A/d Bit Size: 10 bit
• A/d Channels Available: 14
• Height: 4.95 mm
• Length: 53.21 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 1.8 V
• Width: 14.73 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC16F193X/LF193X
19.5.1
The PWM period is specified by the PRx register of
Timerx. The PWM period can be calculated using the
formula of Equation 19-1.
EQUATION 19-1:
When TMRx is equal to PRx, the following three events
occur on the next increment cycle:
• TMRx is cleared
• The CCPx pin is set. (Exception: If the PWM duty
• The PWM duty cycle is latched from CCPRxL into
DS41364A-page 192
cycle = 0%, the pin will not be set.)
CCPRxH.
Note:
PWM Period
Note 1:
PWM PERIOD
The Timerx postscaler (see Section 17.1
“Timer2/4/6 Operation”) is not used in the
determination of the PWM frequency.
T
OSC
=
[
(TMRx Prescale Value)
(
PWM PERIOD
= 1/F
PR2x
OSC
)
+
1
] 4 T
•
•
OSC
•
Preliminary
19.5.2
The PWM duty cycle is specified by writing a 10-bit
value to multiple registers: CCPRxL register and
DCxB<1:0> bits of the CCPxCON register. The
CCPRxL contains the eight MSbs and the DCxB<1:0>
bits of the CCPxCON register contain the two LSbs.
CCPRxL and DCxB<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 PRx and TMRx
registers occurs). While using the PWM, the CCPRxH
register is read-only.
Equation 19-2 is used to calculate the PWM pulse
width.
Equation 19-3 is used to calculate the PWM duty cycle
ratio.
EQUATION 19-2:
EQUATION 19-3:
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 TMRx register is concatenated with either
the 2-bit internal system clock (F
prescaler, to create the 10-bit time base. The system
clock is used if the Timerx 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 19-3).
Duty Cycle Ratio
Pulse Width
PWM DUTY CYCLE
=
(
T
=
CCPRxL:CCPxCON<5:4>
OSC
PULSE WIDTH
DUTY CYCLE RATIO
(
---------------------------------------------------------------------- -
CCPRxL:CCPxCON<5:4>
© 2008 Microchip Technology Inc.
•
(TMRx Prescale Value)
4 PRx
(
OSC
), or 2 bits of the
+
1
)
)
•
)