PIC24FJ16GA MICROCHIP [Microchip Technology], PIC24FJ16GA Datasheet - Page 131

• Manufacturer Part Number: PIC24FJ16GA
• Description: 28/44-Pin General Purpose, 16-Bit Flash Microcontrollers
• Manufacturer: MICROCHIP [Microchip Technology]

EXAMPLE 13-1:
TABLE 13-1:
TABLE 13-2:
© 2008 Microchip Technology Inc.
Timer Prescaler Ratio
Period Register Value
Resolution (bits)
Note 1:
Timer Prescaler Ratio
Period Register Value
Resolution (bits)
Note 1:
1. Find the Timer Period register value for a desired PWM frequency of 52.08 kHz, where F
2.
Note 1:
(32 MHz device clock rate) and a Timer2 prescaler setting of 1:1.
Find the maximum resolution of the duty cycle that can be used with a 52.08 kHz frequency and a 32 MHz device clock rate:
PWM Frequency
PWM Frequency
T
PWM Period = 1/PWM Frequency = 1/52.08 kHz = 19.2 μs
PWM Period = (PR2 + 1) • T
19.2 μs
PR2
PWM Resolution = log
CY
Based on F
Based on F
Based on T
= 2 * Tosc = 62.5 ns
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 4 MIPS (F
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 16 MIPS (F
= (PR2 + 1) • 62.5 ns • 1
= 306
PWM PERIOD AND DUTY CYCLE CALCULATIONS
CY
CY
CY
= (log
= 8.3 bits
= F
= F
= 2 * T
OSC
OSC
10
10
30.5 Hz
FFFFh
/2, Doze mode and PLL are disabled.
FFFFh
/2, Doze mode and PLL are disabled.
OSC
7.6 Hz
(F
(16 MHz/52.08 kHz)/log
16
16
CY
8
8
CY
, Doze mode and PLL are disabled.
/F
• (Timer 2 Prescale Value)
PWM
)/log
244 Hz
FFFFh
FFFFh
61 Hz
16
16
1
1
10
PIC24FJ64GA004 FAMILY
Preliminary
2) bits
10
122 Hz
488 Hz
7FFFh
7FFFh
2) bits
15
15
1
1
3.9 kHz
977 Hz
0FFFh
0FFFh
12
12
1
1
15.6 kHz
(1)
3.9 kHz
03FFh
03FFh
10
10
OSC
1
1
= 8 MHz with PLL
31.3 kHz
125 kHz
007Fh
007Fh
CY
CY
1
7
1
7
DS39881C-page 129
= 4 MHz)
= 16 MHz)
125 kHz
500 kHz
001Fh
001Fh
(1)
1
5
1
5
(1)