4 clock characteristics, 1 accuracy of calibrated internal oscillator, 2 external clock drive – Rainbow Electronics ATtiny10 User Manual
Page 118
118
8127B–AVR–08/09
ATtiny4/5/9/10
16.4
Clock Characteristics
16.4.1
Accuracy of Calibrated Internal Oscillator
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
and
.
Notes:
1. Accuracy of oscillator frequency at calibration point (fixed temperature and fixed voltage).
16.4.2
External Clock Drive
Figure 16-2. External Clock Drive Waveform
Table 16-2.
Calibration Accuracy of Internal RC Oscillator
Calibration
Method
Target Frequency
V
CC
Temperature
Accuracy at given Voltage
& Temperature
(1)
Factory
Calibration
8.0 MHz
3V
25
°
C
±10%
User
Calibration
Fixed frequency within:
7.3 – 8.1 MHz
Fixed voltage within:
1.8V – 5.5V
Fixed temp. within:
-40
°
C – 85
°
C
±1%
V
IL1
V
IH1
Table 16-3.
External Clock Drive Characteristics
Symbol
Parameter
V
CC
= 1.8 - 5.5V
V
CC
= 2.7 - 5.5V
V
CC
= 4.5 - 5.5V
Units
Min.
Max.
Min.
Max.
Min.
Max.
1/t
CLCL
Clock Frequency
0
4
0
10
0
20
MHz
t
CLCL
Clock Period
250
100
50
ns
t
CHCX
High Time
100
40
20
ns
t
CLCX
Low Time
100
40
20
ns
t
CLCH
Rise Time
2.0
1.6
0.5
μ
s
t
CHCL
Fall Time
2.0
1.6
0.5
μ
s
Δ
t
CLCL
Change in period from one clock cycle to the next
2
2
2
%