ATMEGA1284-PU Atmel, ATMEGA1284-PU Datasheet - Page 52

• Manufacturer Part Number: ATMEGA1284-PU
• Description: IC MCU AVR 128K FLASH 40PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA1284-PU

• 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: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.1.2
8272A–AVR–01/10
Power-on Reset
Figure 10-1. Reset Logic
A Power-on Reset (POR) pulse is generated by an On-chip detection circuit. The detection level
is defined in
V
well as to detect a failure in supply voltage.
A Power-on Reset (POR) circuit ensures that the device is reset from Power-on. Reaching the
Power-on Reset threshold voltage invokes the delay counter, which determines how long the
device is kept in RESET after V
when V
164A/164PA/324A/324PA/644A/644PA/1284/1284P
CC
is below the detection level. The POR circuit can be used to trigger the start-up Reset, as
BODLEVEL [2..0]
CC
decreases below the detection level.
”System and Reset Characteristics” on page
Pull-up Resistor
JTAG Reset
Register
FILTER
SPIKE
CC
CKSEL[3:0]
rise. The RESET signal is activated again, without any delay,
Power-on Reset
Reset Circuit
SUT[1:0]
Brown-out
Watchdog
Oscillator
Generator
Circuit
Clock
CK
Register (MCUSR)
MCU Status
DATA BUS
Delay Counters
335. The POR is activated whenever
TIMEOUT
52