ATTINY2313A-MUR Atmel, ATTINY2313A-MUR Datasheet - Page 26

• Manufacturer Part Number: ATTINY2313A-MUR
• Description: MCU AVR 2K FLASH 20MHZ 20QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY2313A-MUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -

6.2.3
26
ATtiny2313A/4313
Calibrated Internal RC Oscillator
Figure 6-2.
When this clock source is selected, start-up times are determined by the SUT Fuses as shown in
Table
Table 6-2.
When applying an external clock, it is required to avoid sudden changes in the applied clock fre-
quency to ensure stable operation of the MCU. A variation in frequency of more than 2% from
one clock cycle to the next can lead to unpredictable behavior. It is required to ensure that the
MCU is kept in Reset during such changes in the clock frequency.
Note that the System Clock Prescaler can be used to implement run-time changes of the internal
clock frequency while still ensuring stable operation. See
for details.
The calibrated internal RC Oscillator provides a fixed 8.0 MHz clock. The frequency is nominal
value at 3V and 25°C. If 8 MHz frequency exceeds the specification of the device (depends on
V
ing start-up. The device is shipped with the CKDIV8 Fuse programmed. This clock may be
selected as the system clock by programming the CKSEL Fuses as shown in
selected, it will operate with no external components. During reset, hardware loads the calibra-
tion byte into the OSCCAL Register and thereby automatically calibrates the RC Oscillator. At
3V and 25°C, this calibration gives a frequency within ± 10% of the nominal frequency. Using
calibration methods as described in application notes available at www.atmel.com/avr it is possi-
ble to achieve ± 2% accuracy at any given V
as the chip clock, the Watchdog Oscillator will still be used for the Watchdog Timer and for the
SUT1..0
CC
), the CKDIV8 Fuse must be programmed in order to divide the internal frequency by 8 dur-
00
01
10
11
6-2.
Start-up Time from Power-
down and Power-save
External Clock Drive Configuration
Start-up Times for the External Clock Selection
6 CK
6 CK
6 CK
EXTERNAL
SIGNAL
CLOCK
NC
Additional Delay from
Reserved
14CK + 64 ms
CC
14CK + 4 ms
and Temperature. When this Oscillator is used
Reset
14CK
XTAL2
XTAL1
GND
“System Clock Prescaler” on page 29
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
8246A–AVR–11/09
Table
6-3. If