ATA6613-EK Atmel, ATA6613-EK Datasheet - Page 171

• Manufacturer Part Number: ATA6613-EK
• Description: BOARD DEMO LIN-MCM FOR ATA6613
• Manufacturer: Atmel

Specifications of ATA6613-EK

• Main Purpose: Interface, LIN + MCU
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6613
• Primary Attributes: LIN-SBC (System-Basis-Chip) Transceiver, LIN 2.0, Voltage Regulator, Window Watchdog
• Secondary Attributes: 16 kB Flash, 4 Power Modes: Pre-Normal, Normal, Sleep, Silent, 48-QFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6.15.6.4
9111H–AUTO–01/11
Phase Correct PWM Mode
The phase correct PWM mode (WGM22:0 = 1 or 5) provides a high resolution phase correct
PWM waveform generation option. The phase correct PWM mode is based on a dual-slope
operation. The counter counts repeatedly from BOTTOM to TOP and then from TOP to BOT-
TOM. TOP is defined as 0xFF when WGM2:0 = 3, and OCR2A when MGM2:0 = 7. In
non-inverting Compare Output mode, the Output Compare (OC2x) is cleared on the compare
match between TCNT2 and OCR2x while upcounting, and set on the compare match while
downcounting. In inverting Output Compare mode, the operation is inverted. The dual-slope
operation has lower maximum operation frequency than single slope operation. However, due
to the symmetric feature of the dual-slope PWM modes, these modes are preferred for motor
control applications.
In phase correct PWM mode the counter is incremented until the counter value matches TOP.
When the counter reaches TOP, it changes the count direction. The TCNT2 value will be
equal to TOP for one timer clock cycle. The timing diagram for the phase correct PWM mode
is shown on
illustrating the dual-slope operation. The diagram includes non-inverted and inverted PWM
outputs. The small horizontal line marks on the TCNT2 slopes represent compare matches
between OCR2x and TCNT2.
Figure 6-59. Phase Correct PWM Mode, Timing Diagram
The Timer/Counter Overflow Flag (TOV2) is set each time the counter reaches BOTTOM. The
Interrupt Flag can be used to generate an interrupt each time the counter reaches the BOT-
TOM value.
TCNTn
OCn
OCn
Period
Figure
6-59. The TCNT2 value is in the timing diagram shown as a histogram for
1
2
Atmel ATA6612/ATA6613
3
(COMnx1:0 = 2)
(COMnx1:0 = 3)
TOVn Interrupt
OCRnx Update
OCnx Interrupt
Flag Set
Flag Set
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