ATmega168 Automotive Atmel Corporation, ATmega168 Automotive Datasheet - Page 30

• Manufacturer Part Number: ATmega168 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega168 Automotive

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 150
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

6.5
6.6
30
Low Frequency Crystal Oscillator
Calibrated Internal RC Oscillator
ATmega48/88/168 Automotive
The device can utilize a 32.768 kHz watch crystal as clock source by a dedicated Low Fre-
quency Crystal Oscillator. The crystal should be connected as shown in
Oscillator is selected, start-up times are determined by the SUT Fuses and CKSEL0 as shown in
Table
Table 6-7.
Note:
The calibrated internal RC Oscillator by default provides a 8.0 MHz clock. The frequency is nom-
inal value at 3V and 25°C. The device is shipped with the CKDIV8 Fuse programmed. See
“System Clock Prescaler” on page 34
clock by programming the CKSEL Fuses as shown in
no external components. During reset, hardware loads the calibration byte into the OSCCAL
Register and thereby automatically calibrates the RC Oscillator. At 3V and 25°C, this calibration
gives a frequency of 8 MHz ± 1%. The tolerance of the internal RC oscillator remains better than
±10% within the whole automotive temperature and voltage ranges (2.7V to 5.5V, -40°C to
+125°C). The oscillator can be calibrated to any frequency in the range 7.3 - 8.1 MHz within ±1%
accuracy, by changing the OSCCAL register. When this Oscillator is used as the chip clock, the
Watchdog Oscillator will still be used for the Watchdog Timer and for the Reset Time-out. For
more information on the pre-programmed calibration value, see the section
page
Table 6-8.
Notes:
Power Conditions
BOD enabled
Fast rising power
Slowly rising power
BOD enabled
Fast rising power
Slowly rising power
282.
6-7.
1. These options should only be used if frequency stability at start-up is not important for the
1. The device is shipped with this option selected.
2. The frequency ranges are preliminary values. Actual values are TBD.
3. If 8 MHz frequency exceeds the specification of the device (depends on V
application.
Fuse can be programmed in order to divide the internal frequency by 8.
Start-up Times for the Low Frequency Crystal Oscillator Clock Selection
Internal Calibrated RC Oscillator Operating Modes
Frequency Range
7.3 - 8.1
Start-up Time from
Power-down and
Reserved
Reserved
Power-save
(2)
32K CK
32K CK
32K CK
1K CK
1K CK
1K CK
(MHz)
for more details. This clock may be selected as the system
Additional Delay
14CK + 4.1 ms
14CK + 65 ms
14CK + 4.1 ms
Table
14CK + 65 ms
(V
from Reset
CC
14CK
14CK
= 5.0V)
6-8. If selected, it will operate with
(1)
(1)(3)
(1)
(1)
CKSEL3..0
Figure
CKSEL0
0010
“Calibration Byte” on
CC
0
0
0
0
1
1
1
1
), the CKDIV8
6-2. When this
7530I–AVR–02/10
SUT1..0
00
01
10
11
00
01
10
11