ATMEGA128A-ANR Atmel, ATMEGA128A-ANR Datasheet - Page 42

• Manufacturer Part Number: ATMEGA128A-ANR
• Description: IC MCU AVR 128K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA128A-ANR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP
• Core: AVR8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.7
8151H–AVR–02/11
Calibrated Internal RC Oscillator
Figure 8-3.
The Oscillator can operate in four different modes, each optimized for a specific frequency
range. The operating mode is selected by the fuses CKSEL3:0 as shown in
Table 8-6.
When this Oscillator is selected, start-up times are determined by the SUT fuses as shown in
Table
Table 8-7.
Note:
The Calibrated Internal RC Oscillator provides a fixed 1.0MHz, 2.0MHz, 4.0MHz, or 8.0MHz
clock. All frequencies are nominal values at 5V and 25
tem clock by programming the CKSEL fuses as shown in
with no external components. The CKOPT fuse should always be unprogrammed when using
this clock option. During Reset, hardware loads the calibration byte for the 1MHz oscillator into
the OSCCAL Register and thereby automatically calibrates the RC Oscillator. At 5V, 25
1.0MHz Oscillator frequency selected, this calibration gives a frequency within ±3% of the nomi-
nal frequency. Using calibration methods as described in application notes available at
www.atmel.com/avr it is possible to achieve ±1% accuracy at any given V
When this Oscillator is used as the chip clock, the Watchdog Oscillator will still be used for the
SUT1:0
00
01
10
11
8-7.
1. This option should not be used when operating close to the maximum frequency of the device.
CKSEL3:0
External RC Configuration
External RC Oscillator Operating Modes
Start-Up Times for the External RC Oscillator Clock Selection
Start-up Time from
Power-down and
0101
0110
0111
1000
Power-save
6CK
18CK
18CK
18CK
(1)
R
C
V
CC
Additional Delay
NC
(V
from Reset
CC
4.1ms
4.1ms
65ms
= 5.0V)
–
°
C. This clock may be selected as the sys-
Frequency Range (MHz)
XTAL2
XTAL1
GND
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
Fast rising power or BOD enabled
Table
8.0 - 12.0
0.1 - 0.9
0.9 - 3.0
3.0 - 8.0
8-8. If selected, it will operate
ATmega128A
CC
Table
and Temperature.
8-6.
°
C and
42