MC68376BGMAB20 Freescale Semiconductor, MC68376BGMAB20 Datasheet - Page 233

• Manufacturer Part Number: MC68376BGMAB20
• Description: IC MCU 32BIT 8K ROM 160-QFP
• Manufacturer: Freescale Semiconductor
• Series: M683xxr

Specifications of MC68376BGMAB20

• Core Processor: CPU32
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: CAN, EBI/EMI, SCI, SPI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Type: ROMless
• Ram Size: 7.5K x 8
• Voltage - Supply (vcc/vdd): 4.75 V ~ 5.25 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 160-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

10.9.9 PWM Pulse Width
10.9.10 PWM Period and Pulse Width Register Values
10.9.10.1 PWM Duty Cycle Boundary Cases
10.9.11 PWMSM Registers
MC68336/376
USER’S MANUAL
The shortest output pulse width (t
equation:
The maximum output pulse width (t
ing equation:
The value loaded into PWMA1 to obtain a given period is:
The value loaded into PWMB1 to obtain a given duty cycle is:
PWM duty cycles 0% and 100% are special boundary cases (zero pulse width and in-
finite pulse width) that are defined by the “always clear” and “always set” states of the
output flip-flop.
A zero width pulse is generated by setting PWMB2 to $0000. The output is a true
steady state signal. An infinite width pulse is generated by setting PWMB2 equal to or
greater than the period value in PWMA2. In both cases, the state of the output pin will
remain unchanged at the polarity defined by the POL bit in PWMSIC.
The PWMSM contains a status/interrupt/control register, a period register, a pulse
width register, and a counter register. All unused bits and reserved address locations
return zero when read. Writes to unused bits and reserved address locations have no
effect. The CTM4 contains four PWMSMs, each with its own set of registers. Refer to
A duty cycle of 100% is not possible when the output period is set to
65536 PWM clock periods (which occurs when PWMB2 is set to
$0000). In this case, the maximum duty cycle is 99.998% (100 x
65535/65536).
Even when the duty cycle is 0% or 100%, the PWMSM counter
continues to count.
PWMB1
t
=
PWMAX
CONFIGURABLE TIMER MODULE 4
----------------------------------
t
PWMIN
PWMA1
t
=
1
PWMIN
PWMIN
N
-------------------------------------------------------------
f
PWMAX
PWM
CLOCK
=
) that can be obtained is given by the following
=
------------------------------------ -
N
=
NOTE
CLOCK
) that can be obtained is given by the follow-
N
------------------- -
Duty Cycle %
----------------------------------- - PWMA1
CLOCK
f
f
N
sys
f
sys
sys
PERIOD
100
f
PWM
–
1
MOTOROLA
10-17