ATMEGA164P-20PQ Atmel, ATMEGA164P-20PQ Datasheet - Page 51

• Manufacturer Part Number: ATMEGA164P-20PQ
• Description: MCU AVR 16K FLASH 20MHZ 40-PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA164P-20PQ

• 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: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K 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: 40-DIP (0.600", 15.24mm)
• For Use With: ATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.3
8011O–AVR–07/10
Power-on Reset
Figure 8-1.
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
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
Reset Logic
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
ATmega164P/324P/644P
Register (MCUSR)
MCU Status
DATA BUS
Delay Counters
331. The POR is activated whenever
TIMEOUT
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