Operating conditions:
- VDD = 3V, unless otherwise
specified
- Oscillator frequencies above speed
specification must be divided, so the CPU clock is always within specification
Table 1. 20 MHz Internal
Oscillator (OSC20M) Characteristics
Symbol |
Description |
Condition |
Min. |
Typ. |
Max. |
Unit |
fOSC20M |
Factory calibration frequency |
FREQSEL = 0x01 |
TA = 25°C, 3.0V |
- |
16 |
- |
MHz |
FREQSEL = 0x02 |
- |
20 |
- |
fCAL |
Frequency calibration range |
OSC20M FREQSEL = 0x01 |
|
14.5 |
- |
17.5 |
MHz |
OSC20M FREQSEL = 0x02 |
|
18.5 |
- |
21.5 |
MHz |
ETOTAL |
Total error with 16 MHz and 20 MHz frequency
selection |
From target frequency |
TA = 25°C, 3.0V |
-1.5 |
- |
1.5 |
% |
TA = [0, 70]°C, VDD = [1.8, 3.6]V |
-2.0(1) |
- |
2.0(1) |
% |
Full operation range |
-3.5 |
- |
3.5 |
ΔfOSC20M |
Calibration step size |
|
|
- |
0.75 |
- |
% |
DOSC20M |
Duty cycle |
|
|
- |
50 |
- |
% |
tstartup |
Start-up time |
Within 2% accuracy |
|
- |
12 |
- |
µs |
Note:
- 1.These values are based on characterization and are not covered by
production test limits.
Table 2. 32.768 kHz Internal
Oscillator (OSCULP32K) Characteristics
Symbol |
Description |
Condition |
Min. |
Typ. |
Max. |
Unit |
fOSCULP32K |
Factory calibration frequency |
|
- |
32.768 |
- |
kHz |
|
Factory calibration accuracy |
TA = 25°C, 3.0V |
-3 |
- |
3 |
% |
ETOTAL |
Total error from target frequency |
TA = [0, 70]°C, VDD = [1.8, 3.6]V |
-10(1) |
- |
+10(1) |
% |
Full operation range |
-20 |
- |
+20 |
DOSCULP32K |
Duty cycle |
|
- |
50 |
- |
% |
tstartup |
Start-up time |
|
- |
250 |
- |
µs |
Note:
- 1.These values are based on characterization and are not covered by
production test limits.
Table 3. 32.768 kHz External
Crystal Oscillator (XOSC32K) Characteristics
Symbol |
Description |
Condition |
Min. |
Typ. |
Max. |
Unit |
fout |
Frequency |
|
- |
32.768 |
- |
kHz |
tstartup |
Start-up time |
CL = 7.5 pF |
- |
300 |
- |
ms |
CL |
Crystal load capacitance |
|
7.5(1) |
- |
12.5(1) |
pF |
ESR |
Equivalent Series Resistance - Safety Factor=3 |
CL = 7.5 pF |
- |
- |
80(1) |
kΩ |
CL = 12.5 pF |
- |
- |
40(1) |
Note:
- 1.This parameter is for design guidance
only. Not production tested.
Figure 1. External Clock Waveform Characteristics
Table 4. External Clock Characteristics
Symbol |
Description |
Condition |
VDD=[1.8,
5.5]V |
VDD=[2.7,
5.5]V |
VDD=[4.5,
5.5]V |
Unit |
Min. |
Max. |
Min. |
Max. |
Min. |
Max. |
fCLCL |
Frequency |
|
0 |
5.0 |
0.0 |
10.0 |
0.0 |
20.0 |
MHz |
tCLCL |
Clock Period |
|
200 |
- |
100 |
- |
50 |
- |
ns |
tCHCX(1) |
High Time |
|
80 |
- |
40 |
- |
20 |
- |
ns |
tCLCX(1) |
Low Time |
|
80 |
- |
40 |
- |
20 |
- |
ns |
tCLCH(1) |
Rise Time (for maximum frequency) |
|
- |
40 |
- |
20 |
- |
10 |
ns |
tCHCL(1) |
Fall Time (for maximum frequency) |
|
- |
40 |
- |
20 |
- |
10 |
ns |
ΔtCLCL(1) |
Change in period from one clock cycle to the next |
|
- |
20 |
- |
20 |
- |
20 |
% |
Note:
- 1.This parameter is for design guidance
only. Not production tested.