attiny25v ATMEL Corporation, attiny25v Datasheet - Page 169

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

21.4
21.4.1
Table 21-2.
21.4.2
Figure 21-3. External Clock Drive Waveforms
21.4.3
Table 21-3.
2586K–AVR–01/08
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
Calibrated Internal RC Oscillator Accuracy
External Clock Drive
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 RC Oscillator
External Clock Drive
Fixed frequency within:
Target Frequency
It is possible to manually calibrate the internal oscillator to be more accurate than default factory
calibration. Please note that the oscillator frequency depends on temperature and voltage. Volt-
age and temperature characteristics can be found in
39 on page
Notes:
8.0 MHz
6 – 8 MHz
V
IL1
V
1. Accuracy of oscillator frequency at calibration point (fixed temperature and fixed voltage).
2. ATtiny25/V, only: 6.4 MHz in ATtiny15 Compatibility Mode.
3. Voltage range for ATtiny25V/45V/85V.
4. Voltage range for ATtiny25/45/85.
IH1
(2)
196.
Fixed voltage within:
1.8V - 5.5V
2.7V - 5.5V
V
3V
CC
V
Min.
250
100
100
(3)
(4)
CC
0
= 1.8 - 5.5V
Max.
2.0
2.0
4
2
Fixed temperature
Temperature
-40°C - 85°C
V
within:
Min.
Figure 22-38 on page 196
25°C
100
CC
40
40
0
= 2.7 - 5.5V
Max.
1.6
1.6
10
2
ATtiny25/45/85
Accuracy at given Voltage
V
Min.
CC
50
20
20
0
& Temperature
= 4.5 - 5.5V
±10%
±1%
Max.
and
0.5
0.5
20
2
Figure 22-
(1)
Units
MHz
ns
ns
ns
μs
μs
%
169