PIC16 datasheet(267/418 Pages) MICROCHIP

267 / 418 page

 2011-2013 Microchip Technology Inc.

DS40001609C-page 267

PIC16(L)F1508/9

23.1.5

PWM RESOLUTION

The resolution determines the number of available duty

cycles for a given period. For example, a 10-bit resolu-

tion will result in 1024 discrete duty cycles, whereas an

8-bit resolution will result in 256 discrete duty cycles.

The maximum PWM resolution is ten bits when PR2 is

255. The resolution is a function of the PR2 register

value as shown by Equation 23-4.

EQUATION 23-4:

PWM RESOLUTION

23.1.6

OPERATION IN SLEEP MODE

In Sleep mode, the TMR2 register will not increment

and the state of the module will not change. If the

PWMx pin is driving a value, it will continue to drive that

value. When the device wakes up, TMR2 will continue

from its previous state.

23.1.7

CHANGES IN SYSTEM CLOCK

FREQUENCY

The PWM frequency is derived from the system clock

frequency (FOSC). Any changes in the system clock fre-

quency will result in changes to the PWM frequency.

Refer to Section 5.0 “Oscillator Module (With

Fail-Safe Clock Monitor)” for additional details.

23.1.8

EFFECTS OF RESET

Any Reset will force all ports to Input mode and the

PWM registers to their Reset states.

Note:

If the pulse width value is greater than the

period the assigned PWM pin(s) will

remain unchanged.

Resolution

4PR2





log



log

------------------------------------------ bits

TABLE 23-1:

EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 20 MHz)

PWM Frequency

0.31 kHz

4.88 kHz

19.53 kHz

78.12 kHz

156.3 kHz

208.3 kHz

Timer Prescale

PR2 Value

0xFF

0x3F

0x1F

0x17

Maximum Resolution (bits)

6.6

TABLE 23-2:

EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 8 MHz)

PWM Frequency

0.31 kHz

4.90 kHz

19.61 kHz

76.92 kHz

153.85 kHz

200.0 kHz

Timer Prescale

PR2 Value

0x65

0x19

0x0C

0x09

Maximum Resolution (bits)

PIC16 Datasheet(PDF) 267 Page - Microchip Technology

PIC16 Datasheet(HTML) 267 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL