ATTINY28L-4AI Atmel, ATTINY28L-4AI Datasheet - Page 15

• Manufacturer Part Number: ATTINY28L-4AI
• Description: IC AVR MCU 2KFLSH 4MHZ 3V 32TQFP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY28L-4AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 11
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Ram Size: -
• Data Converters: -
• Connectivity: -

System Control and
Reset
Reset Sources
1062F–AVR–07/06
The ATtiny28 provides three sources of reset:
•
•
•
During reset, all I/O registers are then set to their initial values and the program starts
execution from address $000. The instruction placed in address $000 must be an RJMP
(relative jump) instruction to the reset handling routine. If the program never enables an
interrupt source, the interrupt vectors are not used, and regular program code can be
placed at these locations. The circuit diagram in Figure 16 shows the reset logic. Table 4
defines the timing and electrical parameters of the reset circuitry.
Figure 16. Reset Logic
Table 4. Reset Characteristics
Note:
Symbol
V
V
RESET
POT
RST
VCC
Power-on Reset. The MCU is reset when the supply voltage is below the Power-on
Reset threshold (V
External Reset. The MCU is reset when a low level is present on the RESET pin for
more than 50 ns.
Watchdog Reset. The MCU is reset when the Watchdog Timer period expires and
the Watchdog is enabled.
(1)
1. The Power-on Reset will not work unless the supply voltage has been below V
(falling).
Parameter
Power-on Reset Threshold Voltage (rising)
Power-on Reset Threshold Voltage (falling)
RESET Pin Threshold Voltage
100 - 500K
POT
RC Oscillator
Reset Circuit
Reset Circuit
).
Power-on
Watchdog
On-chip
Timer
MCU Control and Status
CKSEL[3..0]
Register (MCUCS)
CK
DATA BUS
Delay Counters
Min
1.0
0.4
ATtiny28L/V
0.6 V
Typ
1.4
0.6
Full
CC
R
S
Max
1.8
0.8
Q
Unit
V
V
V
POT
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