MC56F8257MLH Freescale Semiconductor, MC56F8257MLH Datasheet - Page 279

• Manufacturer Part Number: MC56F8257MLH
• Description: DSC 64K FLASH 60MHZ 64-LQFP
• Manufacturer: Freescale Semiconductor
• Series: 56F8xxxr

Specifications of MC56F8257MLH

• Core Processor: 56800E
• Core Size: 16-Bit
• Speed: 60MHz
• Connectivity: CAN, I²C, LIN, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Ram Size: 4K x 16
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 16x12b, D/A 1x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 64-LQFP
• Product: DSCs
• Processor Series: 56800E
• Core: 56800E
• Device Million Instructions Per Second: 60 MIPs
• Maximum Clock Frequency: 60 MHz
• Number Of Programmable I/os: 54
• Data Ram Size: 8 KB
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit, 8 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

The deadtime generators automatically insert software-selectable activation delays into
the pair of PWM outputs. The deadtime registers (DTCNT0 and DTCNT1) specify the
number of IPBus clock cycles to use for deadtime delay. Every time the deadtime
generator inputs change state, deadtime is inserted. Deadtime forces both PWM outputs
in the pair to the inactive state.
When deadtime is inserted in complementary PWM signals connected to an inverter
driving an inductive load, the PWM waveform on the inverter output will have a different
duty cycle than what appears on the output pins of the PWM module. This results in a
distortion in the voltage applied to the load. A method of correcting this, adding to or
subtracting from the PWM value used, is discussed next.
Freescale Semiconductor
VAL1 ($0100)
VAL3
VAL0 ($0000)
VAL2
INIT ($FF00)
no deadtime
with deadtime
PWMB
PWMA
PWMB
PWMA
DTCNT0
MC56F825x/4x Reference Manual, Rev. 2, 10/2010
Figure 7-226. Deadtime Insertion
DTCNT1
Preliminary
Chapter 7 Enhanced Flex Pulse Width Modulator (eFlexPWM)
279