ATMEGA1281V-8MU Atmel, ATMEGA1281V-8MU Datasheet - Page 48

• Manufacturer Part Number: ATMEGA1281V-8MU
• Description: IC MCU AVR 128K FLASH 64-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA1281V-8MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 8K 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-MLF®, 64-QFN
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 8 KB
• Interface Type: 2-Wire, SPI, USART
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 6
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFPATAVRDB101 - MODULE DISPLAY LCD/RGB BACKLIGHT770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.9
2549M–AVR–09/10
External Clock
When this clock source is selected, start-up times are determined by the SUT Fuses as shown in
Table
Table 9-12.
To drive the device from an external clock source, XTAL1 should be driven as shown in
9-4. To run the device on an external clock, the CKSEL Fuses must be programmed to “0000”.
Figure 9-4.
When this clock source is selected, start-up times are determined by the SUT Fuses as shown in
Table 9-15 on page
Table 9-13.
Table 9-14.
When applying an external clock, it is required to avoid sudden changes in the applied clock fre-
quency to ensure stable operation of the MCU. A variation in frequency of more than 2% from
one clock cycle to the next can lead to unpredictable behavior. If changes of more than 2% is
required, ensure that the MCU is kept in Reset during the changes.
Slowly rising power
Slowly rising power
Power Conditions
Power Conditions
Fast rising power
Fast rising power
9-12.
BOD enabled
BOD enabled
Start-up Times for the 128 kHz Internal Oscillator
External Clock Drive Configuration
Crystal Oscillator Clock Frequency
Start-up Times for the External Clock Selection
Nominal Frequency
51.
0 - 16 MHz
EXTERNAL
Start-up Time from Power-
Start-up Time from Power-
SIGNAL
CLOCK
down and Power-save
down and Power-save
ATmega640/1280/1281/2560/2561
NC
Reserved
Reserved
6 CK
6 CK
6 CK
6 CK
6 CK
6 CK
XTAL2
XTAL1
GND
Additional Delay from
Additional Delay from
Reset (V
14CK + 4.1 ms
14CK + 64 ms
14CK + 65 ms
14CK + 4 ms
Reset
14CK
14CK
CC
CKSEL3:0
= 5.0V)
0000
SUT1:0
SUT1:0
00
01
10
11
Figure
00
01
10
11
48