ATmega8535 Atmel Corporation, ATmega8535 Datasheet - Page 29

• Manufacturer Part Number: ATmega8535
• Manufacturer: Atmel Corporation

Specifications of ATmega8535

• Flash (kbytes): 8 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• 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): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• 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: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Calibrated Internal RC
Oscillator
2502K–AVR–10/06
Table 7. External RC Oscillator Operating Modes
When this Oscillator is selected, start-up times are determined by the SUT fuses as
shown in Table 8.
Table 8. Start-up Times for the External RC Oscillator Clock Selection
Note:
The calibrated internal RC Oscillator provides a fixed 1.0, 2.0, 4.0, or 8.0 MHz clock. All
frequencies are nominal values at 5V and 25°C. This clock may be selected as the sys-
tem clock by programming the CKSEL Fuses as shown in Table 9. If selected, it will
operate with no external components. The CKOPT Fuse should always be unpro-
grammed when using this clock option. During Reset, hardware loads the calibration
byte into the OSCCAL Register and thereby automatically calibrates the RC Oscillator.
At 5V, 25°C and 1.0 MHz Oscillator frequency selected, this calibration gives a fre-
quency within ± 3% of the nominal frequency. Using run-time calibration methods as
described in application notes available at www.atmel.com/avr it is possible to achieve
±1% accuracy at any given V
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 “Calibration Byte” on page 239.
Table 9. Internal Calibrated RC Oscillator Operating Modes
Note:
When this Oscillator is selected, start-up times are determined by the SUT Fuses as
shown in Table 10. XTAL1 and XTAL2 should be left unconnected (NC).
SUT1..0
00
01
10
11
1. This option should not be used when operating close to the maximum frequency of
1. The device is shipped with this option selected.
the device.
CKSEL3..0
Start-up Time from
Power-down and
0101
0110
0111
1000
Power-save
CKSEL3..0
6 CK
0001
18 CK
18 CK
18 CK
0010
0011
0100
(1)
(1)
CC
and Temperature. When this Oscillator is used as the
Additional Delay
(V
from Reset
CC
4.1 ms
4.1 ms
65 ms
= 5.0V)
–
Frequency Range (MHz)
Nominal Frequency (MHz)
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
Fast rising power or BOD enabled
8.0 - 12.0
ATmega8535(L)
0.1 - 0.9
0.9 - 3.0
3.0 - 8.0
1.0
2.0
4.0
8.0
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