ATTINY84V-10PU Atmel, ATTINY84V-10PU Datasheet - Page 27

• Manufacturer Part Number: ATTINY84V-10PU
• Description: AVR MCU, 8K FLASH, 512B RAM, 512B EE
• Manufacturer: Atmel

Specifications of ATTINY84V-10PU

• Controller Family/series: AVR Tiny
• No. Of I/o's: 12
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 1KB
• Cpu Speed: 10MHz
• Core Size: 8bit
• Program Memory Size: 8KB
• Oscillator Type: External, Internal
• Processor Series: ATTINY8x
• Core: AVR8
• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Data Ram Size: 512 B
• Interface Type: SPI
• Maximum Clock Frequency: 10 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Package / Case: PDIP-14
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.2
7.3
7.4
8006F–AVR–02/07
Clock Sources
Default Clock Source
Crystal Oscillator
The device has the following clock source options, selectable by Flash Fuse bits as shown
below. The clock from the selected source is input to the AVR clock generator, and routed to the
appropriate modules.
Table 7-1.
Note:
The various choices for each clocking option is given in the following sections. When the CPU
wakes up from Power-down or Power-save, the selected clock source is used to time the start-
up, ensuring stable Oscillator operation before instruction execution starts. When the CPU starts
from reset, there is an additional delay allowing the power to reach a stable level before com-
mencing normal operation. The Watchdog Oscillator is used for timing this real-time part of the
start-up time. The number of WDT Oscillator cycles used for each time-out is shown in
on page
Table 7-2.
The device is shipped with CKSEL = “0010”, SUT = “10”, and CKDIV8 programmed. The default
clock source setting is therefore the Internal RC Oscillator running at 8.0 MHz with longest start-
up time and an initial system clock prescaling of 8, resulting in 1.0 MHz system clock. This
default setting ensures that all users can make their desired clock source setting using an In-
System or High-voltage Programmer.
XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier which can
be configured for use as an On-chip Oscillator, as shown in Figure 7-2. Either a quartz
crystal or a ceramic resonator may be used.
C1 and C2 should always be equal for both crystals and resonators. The optimal value of the
capacitors depends on the crystal or resonator in use, the amount of stray capac-itance, and the
electromagnetic noise of the environment. Some initial guidelines for choosing capacitors for
use with crystals are given in
ues given by the manufacturer should be used.
Device Clocking Option
External Clock
Calibrated Internal RC Oscillator 8.0 MHz
Watchdog Oscillator 128 kHz
External Low-frequency Oscillator
External Crystal/Ceramic Resonator
Reserved
1. For all fuses “1” means unprogrammed while “0” means programmed.
27.
Typ Time-out
Device Clocking Options Select
Number of Watchdog Oscillator Cycles
64 ms
4 ms
Table 7-3 on page
(1)
28. For ceramic resonators, the capacitor val-
Number of Cycles
8K (8,192)
512
ATtiny24/44/84
0101, 0111, 0011,0001
CKSEL3..0
1000-1111
0000
0010
0100
0110
Table 7-2
27