37.10.1 Internal Oscillators

Table 37-10. Internal Oscillators Specifications⁽¹⁾
Symbol	Description	Min.	Typ. ✝	Max.	Unit	Conditions
f_OSCHF	OSCHF frequency	—	1⁽²⁾ 2⁽²⁾ 3⁽²⁾	—	MHz
f_OSCHF	Precision calibrated OSCHF frequency	—	4 8 12 16 20 24	—	MHz
%_CAL	OSCHF tune step size	—	0.4	—	%
t_{OSCHF_ST⁽³⁾}	OSCHF wake-up from sleep start-up time	—	24	30	μs	Device in Idle or Standby sleep mode, VREGCTRL.PMODE = FULL
t_{OSCHF_ST⁽³⁾}	OSCHF wake-up from sleep start-up time	—	115	180	μs	Device in Power-Down sleep mode, VREGCTRL.PMODE = AUTO
f_OSC32K	Internal OSC32K frequency	—	32.768	—	kHz
t_{OSC32K_ST}⁽³⁾	OSC32K wake-up from sleep start-up time	—	950	1000	μs	Device in Power-Down sleep mode, VREGCTRL.PMODE = AUTO
✝ Data in the “Typ.” column is at T_A = 25°C and V_DD = 3.0V unless otherwise specified. These parameters are not tested and are for design guidance only. Note: To ensure these oscillator frequency tolerances, V_DD and GND must be capacitively decoupled as close to the device as possible. 100 nF and 0.1 μF values in parallel are recommended. These parameters are not calibrated. Wake-up times are measured from the wake-up event to code execution.

Figure 37-2. Precision Calibrated OSCHF (4 MHz) Frequency Accuracy Over Device V_DD and Temperature