ATMEGA8A-AUR Atmel, ATMEGA8A-AUR Datasheet - Page 249

• Manufacturer Part Number: ATMEGA8A-AUR
• Description: MCU AVR 8KB FLASH 16MHZ 32TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8A-AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 8KB (4K 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: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

25.7
8159D–AVR–02/11
2. Required only for f
3. C
4. f
5. This requirement applies to all ATmega8A Two-wire Serial Interface operation. Other devices connected to the Two-wire
6. The actual low period generated by the ATmega8A Two-wire Serial Interface is (1/f
7. The actual low period generated by the ATmega8A Two-wire Serial Interface is (1/f
SPI Timing Characteristics
Serial Bus need only obey the general f
6MHz for the low time requirement to be strictly met at f
will not be strictly met for f
at full speed (400kHz) with other ATmega8A devices, as well as any other device with a proper t
CK
b
= capacitance of one bus line in pF.
= CPU clock frequency
Figure 25-3. Two-wire Serial Bus Timing
See
Table 25-5.
SCL
10
11
12
13
14
15
16
17
18
1
2
3
4
5
6
7
8
9
SCL
SDA
Figure 25-4
> 100kHz.
SCL
t
SU;STA
> 308kHz when f
SS high to tri-state
SCK to out high
SCK to SS high
SCK high/low
SS low to SCK
SCK high/low
Rise/Fall time
Rise/Fall time
SS low to out
Description
SPI Timing Parameters
SCK period
SCK period
Out to SCK
SCK to out
SCK to out
and
Setup
Setup
Hold
Hold
SCL
Figure 25-5
requirement.
(1)
t
CK
HD;STA
= 8MHz. Still, ATmega8A devices connected to the bus may communicate
t
of
t
LOW
for details.
SCL
Master
Master
Master
Master
Master
Master
Master
Master
Mode
Slave
Slave
Slave
Slave
Slave
Slave
Slave
Slave
Slave
Salve
= 100kHz.
t
HIGH
t
HD;DAT
t
LOW
4 • t
2 • t
2 • t
Min
10
10
20
ck
ck
ck
t
SU;DAT
SCL
SCL
See
50% duty cycle
- 2/f
- 2/f
0.5 • t
CK
CK
Table 18-4
Typ
3.6
), thus the low time requirement
10
10
10
10
15
15
10
), thus f
SCK
LOW
CK
acceptance margin.
t
ATmega8A
SU;STO
must be greater than
t
r
Max
1.6
t
BUF
ns
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