ATTINY24A-MFR Atmel, ATTINY24A-MFR Datasheet - Page 39

• Manufacturer Part Number: ATTINY24A-MFR
• Description: MCU AVR 2KB FLASH 20MHZ 20QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY24A-MFR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 12
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 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: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.2
8.2.1
8183C–AVR–03/11
Reset Sources
Power-on Reset
The ATtiny24A/44A/84A 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
V
Figure 8-2.
Figure 8-3.
CC
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 when RESET function is enabled
Watchdog is enabled
Reset threshold (V
is below the detection level. The POR circuit can be used to trigger the Start-up Reset, as
decreases below the detection level.
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
RESET
RESET
V
V
CC
CC
“System and Reset Characteristics” on page
POT
MCU Start-up, RESET Tied to V
MCU Start-up, RESET Extended Externally
)
BOT
) and the Brown-out Detector is enabled
V
V
V
CC
POT
POT
RST
rise. The reset signal is activated again, without any delay, when
t
TOUT
V
RST
CC
t
TOUT
176. The POR is activated whenever
ATtiny24A/44A/84A
CC
is below the Brown-out
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