ATTINY261A-MU Atmel, ATTINY261A-MU Datasheet - Page 186

• Manufacturer Part Number: ATTINY261A-MU
• Description: NO NEW DESIGNS, USE TINY261A-XU - 20MHZ, QFN/MLF,IND TEMP, G
• Manufacturer: Atmel

19.4
19.4.1
Table 19-2.
Notes:
19.4.2
Figure 19-2. External Clock Drive Waveforms
Table 19-3.
186
Calibration
Method
Factory
Calibration
User
Calibration
Symbol
1/t
t
t
t
t
t
Δ
CLCL
CHCX
CLCX
CLCH
CHCL
t
CLCL
CLCL
Clock Characteristics
1. Accuracy of oscillator frequency at calibration point (fixed temperature and fixed voltage).
ATtiny261A/461A/861A
Accuracy of Calibrated Internal Oscillator
External Clock Drive
Parameter
Clock Frequency
Clock Period
High Time
Low Time
Rise Time
Fall Time
Change in period from one clock cycle to the next
Calibration Accuracy of Internal Oscillator
External Clock Drive Characteristics
V
IL1
V
It is possible to manually calibrate the internal oscillator to be more accurate than default factory
calibration. Note that the oscillator frequency depends on temperature and voltage. Voltage and
temperature characteristics can be found in
page
Target Frequency
IH1
Fixed frequency
7.3 - 8.1 MHz
219.
8.0 MHz
within:
Fixed voltage within:
1.8V - 5.5V
V
3V
CC
V
Min.
250
100
100
CC
0
= 1.8 - 5.5V
Max.
2.0
2.0
4
2
Figure 20-49 on page 219
Fixed temperature
Temperature
-40°C - 85°C
within:
25°C
V
Min.
100
CC
40
40
0
= 2.7 - 5.5V
Max.
1.6
1.6
10
2
voltage & temperature
V
Min.
CC
Accuracy at given
50
20
20
0
and
= 4.5 - 5.5V
±10%
Figure 20-50 on
±1%
Max.
0.5
0.5
20
8197B–AVR–01/10
2
Units
MHz
ns
ns
ns
μs
μs
%
(1)