ATMEGA1284P-AU Atmel, ATMEGA1284P-AU Datasheet - Page 38

• Manufacturer Part Number: ATMEGA1284P-AU
• Description: MCU AVR 128K ISP FLASH 44-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA1284P-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 16K 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: 44-TQFP, 44-VQFP
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 16 KB
• Interface Type: 2-Wire, SPI, USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRRAVEN, ATAVRRZUSBSTICK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Package: 44TQFP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 20 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Rom Size: 4 KB
• Height: 1.05 mm
• Length: 10.1 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 1.8 V
• Width: 10.1 mm
• Controller Family/series: AVR MEGA
• No. Of I/o's: 32
• Eeprom Memory Size: 4KB
• Ram Memory Size: 16KB
• Cpu Speed: 20MHz
• Rohs Compliant: Yes
• For Use With: ATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600 - DEV KIT FOR AVR/AVR32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.7
8.8
8272A–AVR–01/10
128 kHz Internal Oscillator
External Clock
The 128 kHz internal Oscillator is a low power Oscillator providing a clock of 128 kHz. The fre-
quency is nominal at 3V and 25°C. This clock may be select as the system clock by
programming the CKSEL Fuses to “0011” as shown in
Table 8-12.
Note:
When this clock source is selected, start-up times are determined by the SUT Fuses as shown in
Table
Table 8-13.
To drive the device from an external clock source, XTAL1 should be driven as shown in
8-4. To run the device on an external clock, the CKSEL Fuses must be programmed to “0000”.
Figure 8-4.
When this clock source is selected, start-up times are determined by the SUT Fuses as shown in
Table
164A/164PA/324A/324PA/644A/644PA/1284/1284P
BOD enabled
Fast rising power
Slowly rising power
Power Conditions
8-13.
8-15.
1. Note that the 128kHz oscillator is a very low power clock source, and is not designed for high
accuracy.
128 kHz Internal Oscillator Operating Modes
Start-up Times for the 128 kHz Internal Oscillator
External Clock Drive Configuration
Nominal Frequency
EXTERNAL
128 kHz
SIGNAL
CLOCK
Start-up Time from Power-
down and Power-save
NC
Reserved
6 CK
6 CK
6 CK
XTAL2
XTAL1
GND
Table
(2)
Additional Delay from
8-12.
14CK + 64 ms
14CK + 4 ms
Reset
14CK
CKSEL3..0
0011
SUT1..0
00
01
10
11
Figure
38