ATMEGA645V-8AU Atmel, ATMEGA645V-8AU Datasheet - Page 120

• Manufacturer Part Number: ATMEGA645V-8AU
• Description: IC AVR MCU FLASH 64K 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA645V-8AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Processor Series: ATMEGA64x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, UART, USI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 3
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Controller Family/series: AVR MEGA
• No. Of I/o's: 54
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 8MHz
• No. Of Timers: 3
• Rohs Compliant: Yes
• Data Rom Size: 2 KB
• Height: 1 mm
• Length: 14 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Width: 14 mm
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2570M–AVR–04/11
the maximum resolution is 16-bit (ICR1 or OCR1A set to MAX). The PWM resolution in bits can
be calculated using the following equation:
In phase and frequency correct PWM mode the counter is incremented until the counter value
matches either the value in ICR1 (WGM13:0 = 8), or the value in OCR1A (WGM13:0 = 9). The
counter has then reached the TOP and changes the count direction. The TCNT1 value will be
equal to TOP for one timer clock cycle. The timing diagram for the phase correct and frequency
correct PWM mode is shown on
PWM mode when OCR1A or ICR1 is used to define TOP. The TCNT1 value is in the timing dia-
gram shown as a histogram for illustrating the dual-slope operation. The diagram includes non-
inverted and inverted PWM outputs. The small horizontal line marks on the TCNT1 slopes repre-
sent compare matches between OCR1x and TCNT1. The OC1x Interrupt Flag will be set when a
compare match occurs.
Figure 16-9. Phase and Frequency Correct PWM Mode, Timing Diagram
The Timer/Counter Overflow Flag (TOV1) is set at the same timer clock cycle as the OCR1x
Registers are updated with the double buffer value (at BOTTOM). When either OCR1A or ICR1
is used for defining the TOP value, the OC1A or ICF1 Flag set when TCNT1 has reached TOP.
The Interrupt Flags can then be used to generate an interrupt each time the counter reaches the
TOP or BOTTOM value.
When changing the TOP value the program must ensure that the new TOP value is higher or
equal to the value of all of the Compare Registers. If the TOP value is lower than any of the
Compare Registers, a compare match will never occur between the TCNT1 and the OCR1x.
As
cal in all periods. Since the OCR1x Registers are updated at BOTTOM, the length of the rising
and the falling slopes will always be equal. This gives symmetrical output pulses and is therefore
frequency correct.
Figure 16-9
TCNTn
OCnx
OCnx
Period
shows the output generated is, in contrast to the phase correct mode, symmetri-
1
Figure
R
PFCPWM
2
16-9. The figure shows phase and frequency correct
ATmega325/3250/645/6450
=
3
log
---------------------------------- -
(
log
TOP
2 ( )
+
1
4
)
OCnA Interrupt Flag Set
or ICFn Interrupt Flag Set
(Interrupt on TOP)
(COMnx1:0 = 2)
(COMnx1:0 = 3)
OCRnx/TOP Updateand
TOVn Interrupt Flag Set
(Interrupt on Bottom)
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