ATTINY461-20PU Atmel, ATTINY461-20PU Datasheet - Page 42

• Manufacturer Part Number: ATTINY461-20PU
• Description: Microcontrollers (MCU) 4kB Flash 0.256kB EEPROM 16 I/O Pins
• Manufacturer: Atmel

Specifications of ATTINY461-20PU

• Processor Series: ATTINY4x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: 2-Wire/SPI/USI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 2
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 11-ch x 10-bit
• Program Memory Type: Flash
• Program Memory Size: 4 KB
• Package / Case: PDIP-20
• Package: 20PDIP
• Device Core: AVR
• Family Name: ATtiny
• Maximum Speed: 20 MHz
• Ram Size: 256 Byte
• Operating Temperature: -40 to 85 °C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.1
8.1.1
42
Reset Sources
ATtiny261/461/861
Power-on Reset
The ATtiny261/461/861 has four sources of reset:
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
Figure 8-2.
Figure 8-3.
CC
• Power-on Reset. The MCU is reset when the supply voltage is below the Power-on Reset
• External Reset. The MCU is reset when a low level is present on the RESET pin for longer
• Watchdog Reset. The MCU is reset when the Watchdog Timer period expires and the
• Brown-out Reset. The MCU is reset when the supply voltage V
threshold (V
than the minimum pulse length.
Watchdog is enabled.
Reset threshold (V
is below the detection level. The POR circuit can be used to trigger the Start-up Reset, as
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
CC
RESET
RESET
RESET
RESET
V
V
decreases below the detection level.
CC
CC
“System and Reset Characteristics” on page
MCU Start-up, RESET Tied to V
MCU Start-up, RESET Extended Externally
POT
).
BOT
) and the Brown-out Detector is enabled.
V
V
V
POT
POT
RST
CC
t
TOUT
rise. The RESET signal is activated again, without any delay,
CC
V
RST
t
TOUT
190. The POR is activated whenever
CC
is below the Brown-out
2588E–AVR–08/10