S9S12G240F0CLFR Freescale Semiconductor, S9S12G240F0CLFR Datasheet - Page 658

• Manufacturer Part Number: S9S12G240F0CLFR
• Description: 16-bit Microcontrollers - MCU 16BIT 240KB FLASH
• Manufacturer: Freescale Semiconductor

Specifications of S9S12G240F0CLFR

• Rohs: yes
• Core: S12
• Processor Series: MC9S12G
• Data Bus Width: 16 bit
• Maximum Clock Frequency: 25 MHz
• Program Memory Size: 240 KB
• Data Ram Size: 4 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3.13 V to 5.5 V
• Operating Temperature Range: - 40 C to + 125 C
• Package / Case: LQFP-48
• Mounting Style: SMD/SMT

Pulse-Width Modulator (S12PWM8B8CV2)
To calculate the output frequency in left aligned output mode for a particular channel, take the selected
clock source frequency for the channel (A, B, SA, or SB) and divide it by the value in the period register
for that channel.
As an example of a left aligned output, consider the following case:
The output waveform generated is shown in
660
•
•
PWMx Frequency = Clock (A, B, SA, or SB) / PWMPERx
PWMx Duty Cycle (high time as a% of period):
— Polarity = 0 (PPOLx = 0)
— Polarity = 1 (PPOLx = 1)
Clock Source = E, where E = 10 MHz (100 ns period)
PPOLx = 0
PWMPERx = 4
PWMDTYx = 1
PWMx Frequency = 10 MHz/4 = 2.5 MHz
PWMx Period = 400 ns
PWMx Duty Cycle = 3/4 *100% = 75%
Duty Cycle = [(PWMPERx-PWMDTYx)/PWMPERx] * 100%
Duty Cycle = [PWMDTYx / PWMPERx] * 100%
Changing the PWM output mode from left aligned to center aligned output
(or vice versa) while channels are operating can cause irregularities in the
PWM output. It is recommended to program the output mode before
enabling the PWM channel.
PPOLx = 0
PPOLx = 1
E = 100 ns
Figure 19-18. PWM Left Aligned Output Example Waveform
Figure 19-17. PWM Left Aligned Output Waveform
MC9S12G Family Reference Manual,
PWMDTYx
Period = 400 ns
Figure
Period = PWMPERx
Duty Cycle = 75%
NOTE
19-18.
Rev.1.23
Freescale Semiconductor