Oscillators and Clocks

Operating conditions:
Table 1. 20MHz Internal Oscillator (OSC20M) Characteristics
Symbol Description Condition Min. Typ. Max. Unit
fOSC20M Accuracy with 16MHz Frequency Selection Factory calibrated T=25°C, 3.0V TBD ±1.5 TBD %
T=[0, 70]°C, VDD=[1.8, 3.6]V TBD ±2 TBD
Full operation range TBD ±3 TBD
Accuracy with 20MHz Frequency Selection Factory calibrated T=25C, 3.0V TBD ±1.5 TBD
T=[0, 70]°C, VDD=[1.8, 3.6]V TBD ±2 TBD
Full operation range TBD ±3 TBD
Accuracy with 16MHz Frequency Selection with factory-stored frequency error value Factory calibrated VDD=3V(1) T=[0, 70]°C, VDD=[1.8, 4.5]V TBD ±1.5 TBD %
Factory calibrated VDD=5V(1) T=[0, 70]°C, VDD=[4.5, 5.5]V TBD ±1.5 TBD
Accuracy with 20MHz Frequency Selection with factory-stored frequency error value Factory calibrated VDD=3V(1) T=[0, 70]°C, VDD=[1.8, 4.5]V TBD ±1.5 TBD
Factory calibrated VDD=5V(1) T=[0, 70]°C, VDD=[4.5, 5.5]V TBD ±1.5 TBD
fCAL User calibration range OSC16M(2)   14.5   17.5 MHz
OSC20M(2)   18.5   21.5 MHz
%CAL Calibration step size   - 1.5 - %
DC Duty cycle   - 50 - %
Tstart Start-up time Within 2% accuracy   - 8 - µs
Note:
  1. 1.See also description of OSC20M on calibration.
  2. 2.Oscillator Frequencies above speed specification must be divided so that CPU clock always is within specification.
Table 2. 32.768kHz Internal Oscillator (OSCULP32K) Characteristics
Symbol Description Condition Condition Min. Typ. Max. Unit
fOSCULP32K Accuracy Factory calibrated T=25°C, 3.0V TBD ±2 TBD %
T=[0, 70]°C, VDD=[1.8, 3.6]V -10 ±5 +10
Full operation range -30 ±10 +30
DC Duty cycle     - 50 - %
Tstart Start-up time     - 250 - µs
Table 3. 32.768kHz External Crystal Oscillator (XOSC32K) Characteristics
Symbol Description Condition Min. typ Max. Unit
Fout Frequency - 32.768 - kHz
Tstart Startup time CL=7.5pF - 300 - ms
CL=12.5pF - TBD -  
CL Crystal load capacitance 7.5 - 12.5 pF
CTOSC1 Parasitic capacitor load - 5.5 - pF
CTOSC2 - 5.5 - pF
ESR Equivalent Series Resistance - Safety Factor=3 CL=7.5pF - - 80 kΩ
CL=12.5pF - - 40
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 High Time 80 - 40 - 20 - ns
tCLCX Low Time 80 - 40 - 20 - ns
tCLCH Rise Time - 2.0 - 1.6 - 0.5 µs
tCHCL Fall Time - 2.0 - 1.6 - 0.5 µs
ΔtCLCL Change in period from one clock cycle to the next - 2 - 2 - 2 %