ATMEGA645A-AU Atmel, ATMEGA645A-AU Datasheet - Page 325

• Manufacturer Part Number: ATMEGA645A-AU
• Description: IC MCU AVR 64K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA645A-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• 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
• Processor Series: ATmega
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 3
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

27.4
27.4.1
Table 27-11. Calibration Accuracy of Internal RC Oscillator
Notes:
27.4.2
27.4.3
8285B–AVR–03/11
Factory Calibration
User Calibration
Clock Characteristics
1. Voltage range for ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P.
Calibrated Internal RC Oscillator Accuracy
External Clock Drive Waveforms
External Clock Drive
ATmega165A/165PA/325A/325PA/3250A/3250PA/6
Figure 27-3. External Clock Drive Waveforms
Table 27-12. External Clock Drive
Symbol
1/t
t
t
t
t
t
Δ
CLCL
CHCX
CLCX
CLCH
CHCL
t
CLCL
CLCL
7.3 - 8.1MHz
Frequency
8.0MHz
Parameter
Oscillator
Frequency
Clock Period
High Time
Low Time
Rise Time
Fall Time
Change in period
from one clock
cycle to the next
V
IL1
V
IH1
1.8V - 5.5V
V
3V
1000
Min.
400
400
V
CC
0
CC
=1.8-5.5V
(1)
Max.
2.0
2.0
4
2
Min.
100
V
Temperature
40
40
-40°C - 85°C
0
CC
=2.7-5.5V
25°C
Max.
1.6
1.6
10
2
Min.
V
50
20
20
0
CC
Calibration Accuracy
=4.5-5.5V
Max.
±10%
0.5
0.5
20
±1%
2
Units
MHz
ns
ns
ns
μs
μs
%
325