ATTINY13-20PJ Atmel, ATTINY13-20PJ Datasheet - Page 25

• Manufacturer Part Number: ATTINY13-20PJ
• Description: IC MCU AVR 1K 5V 20MHZ 8DIP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY13-20PJ

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 6
• Program Memory Size: 1KB (512 x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 64 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Connectivity: -
• Other names: ATTINY13-24PJ; ATTINY13-24PJ

6.2.2
2535J–AVR–08/10
Calibrated Internal 4.8/9.6 MHz Oscillator
When this clock source is selected, start-up times are determined by the SUT fuses as shown in
Table
Table 6-3.
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. Refer to
26
The calibrated internal oscillator provides a 4.8 or 9.6 MHz clock source. The frequency is nomi-
nal at 3V and 25°C. If the frequency exceeds the specification of the device (depends on V
the CKDIV8 fuse must be programmed so that the internal clock is divided by 8 during start-up.
See “System Clock Prescaler” on page 26.
The internal oscillator is selected as the system clock by programming the CKSEL fuses as
shown in
Table 6-4.
Note:
During reset, hardware loads the calibration data into the OSCCAL register and thereby auto-
matically calibrates the oscillator. There are separate calibration bytes for 4.8 and 9.6 MHz
operation but only one is automatically loaded during reset (see section
page
nal clock divider.
By changing the OSCCAL register from SW, see
page
See
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 cali-
bration value, see the section
SUT1..0
for details.
00
01
10
11
“Calibrated Internal RC Oscillator Accuracy” on page
104). This is because the only difference between 4.8 MHz and 9.6 MHz mode is an inter-
27, it is possible to get a higher calibration accuracy than by using the factory calibration.
6-3.
1. The device is shipped with this option selected.
Table
Power-down and Power-save
Start-up Times for the External Clock Selection
Internal Calibrated RC Oscillator Operating Modes
6-4. If selected, it will operate with no external components.
Start-up Time from
CKSEL1..0
10
01
(1)
6 CK
6 CK
6 CK
“Calibration Bytes” on page
for more details.
Additional Delay
Reserved
“OSCCAL – Oscillator Calibration Register” on
14CK + 64 ms
14CK + 4 ms
from Reset
14CK
118.
104.
“System Clock Prescaler” on page
Nominal Frequency
9.6 MHz
4.8 MHz
BOD enabled
Fast rising power
Slowly rising power
“Calibration Bytes” on
Recommended
Usage
CC
25
),