ATMEGA649V-8MUR Atmel, ATMEGA649V-8MUR Datasheet - Page 25
![MCU AVR 64KB FLASH 8MHZ 64QFN](/photos/12/13/121326/313-64-qfn_sml.jpg)
ATMEGA649V-8MUR
Manufacturer Part Number
ATMEGA649V-8MUR
Description
MCU AVR 64KB FLASH 8MHZ 64QFN
Manufacturer
Atmel
Series
AVR® ATmegar
Datasheet
1.ATMEGA329-16AU.pdf
(30 pages)
Specifications of ATMEGA649V-8MUR
Core Processor
AVR
Core Size
8-Bit
Speed
8MHz
Connectivity
SPI, UART/USART, USI
Peripherals
Brown-out Detect/Reset, LCD, 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
*
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
10.2
10.2.1
10.2.2
10.2.3
2552KS–AVR–04/11
ATmega3290
ATmega3290 rev. C
ATmega3290 rev. B
ATmega3290 rev. A
•
1. Interrupts may be lost when writing the timer registers in the asynchronous timer
Not sampled.
•
•
1. LCD contrast voltage too high
2. Interrupts may be lost when writing the timer registers in the asynchronous timer
Interrupts may be lost when writing the timer registers in the asynchronous timer
LCD contrast voltage too high
Interrupts may be lost when writing the timer registers in the asynchronous timer
The interrupt will be lost if a timer register that is synchronous timer clock is written when the
asynchronous Timer/Counter register (TCNTx) is 0x00.
Problem Fix/Wortkaround
Always check that the asynchronous Timer/Counter register neither have the value 0xFF nor
0x00 before writing to the asynchronous Timer Control Register (TCCRx), asynchronous
Timer Counter Register (TCNTx), or asynchronous Output Compare Register (OCRx).
When the LCD is active and using low power waveform, the LCD contrast voltage can be too
high. This occurs when V
Problem Fix/Workaround
There are several possible workarounds:
- Use normal waveform instead of low power waveform
- Use drivetime of 375 µs or longer
The interrupt will be lost if a timer register that is synchronous timer clock is written when the
asynchronous Timer/Counter register (TCNTx) is 0x00.
Problem Fix/Wortkaround
Always check that the asynchronous Timer/Counter register neither have the value 0xFF nor
0x00 before writing to the asynchronous Timer Control Register (TCCRx), asynchronous
Timer Counter Register (TCNTx), or asynchronous Output Compare Register (OCRx).
CC
is higher than V
ATmega329/3290/649/6490
LCD
, and when using low LCD drivetime.
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