ATTINY43U-SUR Atmel, ATTINY43U-SUR Datasheet - Page 49

• Manufacturer Part Number: ATTINY43U-SUR
• Description: MCU AVR 4KB FLASH 8MHZ 20SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY43U-SUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 16
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.2
9.3
8048B–AVR–03/09
Reset Sources
Power-on Reset
The ATtiny43U 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
level. The POR circuit can be used to trigger the Start-up Reset, as 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 9-2.
Figure 9-3.
• 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
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
CC
RESET
RESET
RESET
RESET
V
V
decreases below the detection level.
CC
CC
Table 20-4 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
158. The POR is activated whenever V
t
TOUT
rise. The RESET signal is activated again, without any delay,
CC
V
RST
t
TOUT
CC
is below the Brown-out
CC
is below the detection
49