ATtiny26 Atmel Corporation, ATtiny26 Datasheet - Page 26

• Manufacturer Part Number: ATtiny26
• Manufacturer: Atmel Corporation

Specifications of ATtiny26

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 11
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: NO
• 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: 2
• Output Compare Channels: 3
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

Default Clock
Source
Crystal Oscillator
26
ATtiny26(L)
quency of the Watchdog Oscillator is voltage dependent as shown in the Electrical
Characteristics section.
Table 5. Number of Watchdog Oscillator Cycles
The deviced is shipped with CKSEL = “0001”, SUT = “10”, and PLLCK unprogrammed. The
default clock source setting is therefore the internal RC Oscillator with longest startup time. This
default setting ensures that all users can make their desired clock source setting using an In-
System or Parallel Programmer.
XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier which can be con-
figured for use as an On-chip Oscillator, as shown in Figure 22. Either a quartz crystal or a
ceramic resonator may be used. The maximum frequency for resonators is 12 MHz. The
CKOPT Fuse should always be unprogrammed when using this clock option. C1 and C2 should
always be equal. The optimal value of the capacitors depends on the crystal or resonator in use,
the amount of stray capacitance, and the electromagnetic noise of the environment. Some initial
guidelines for choosing capacitors for use with crystals are given in Table 6. For ceramic resona-
tors, the capacitor values given by the manufacturer should be used.
Figure 22. Crystal Oscillator Connections
The Oscillator can operate in three different modes, each optimized for a specific frequency
range. The operating mode is selected by the fuses CKSEL3..1 as shown in Table 6.
Table 6. Crystal Oscillator Operating Modes
Note:
CKSEL3..1
Typ Time-out (V
101
110
111
(1)
1. This option should not be used with crystals, only with ceramic resonators.
4.1 ms
65 ms
CC
Range (MHz)
Frequency
= 5.0V)
0.4 - 0.9
0.9 - 3.0
3.0 - 16
16 -
Typ Time-out (V
C2
C1
Recommended Range for Capacitors C1 and
4.3 ms
69 ms
C2 for Use with Crystals (pF)
CC
= 3.0V)
XTAL2
XTAL1
GND
12 - 22
12 - 22
12 - 15
–
Number of Cycles
64K (65,536)
4K (4,096)
1477K–AVR–08/10