46.13.1 Crystal Oscillator (XOSC) Characteristics

Digital Clock Characteristics

The following table describes the characteristics for the oscillator when a digital clock is applied on XIN.

Table 46-44. Digital Clock Characteristics
Symbol	Parameter	Min.	Typ.	Max.	Units
F_XIN	XIN clock frequency	-	-	24	MHz
DC_XIN⁽¹⁾	XIN clock duty cycle	40	50	60	%

Note:

These values are based on simulation. They are not covered by production test limits or characterization.

Crystal Oscillator Characteristics

The following Table describes the characteristics for the oscillator when a crystal is connected between XIN and XOUT.

The user must choose a crystal oscillator where the crystal load capacitance C_L is within the range given in the Table. The exact value of C_L can be found in the crystal data sheet. The capacitance of the external capacitors (C_LEXT) can then be computed as follows:

C_LEXT = 2(C_L - C_PARA - C_PCB - C_SHUNT)

Where:

C_PARA is the internal load capacitor parasitic between XIN and XOUT (C_PARA = (C_XIN * C_XOUT)/(C_XIN + C_XOUT))
C_PCB is the capacitance of the PCB
C_SHUNT is the shunt capacity of the crystal.

Table 46-45. Multi Crystal Oscillator Electrical Characteristics
Symbol	Parameter	Conditions	Min.	Typ.	Max	Units
Fout	Crystal oscillator frequency		0.4	-	32	MHz
ESR⁽²⁾	Crystal Equivalent Series Resistance - SF = 3	F = 0,4MHz - CL=100 pF XOSC,GAIN=0	-	-	5.6K	Ω
		F = 2MHz - CL=20 pF XOSC,GAIN=0, Cshunt=3.3pF	-	-	330
		F = 4MHz - CL=20 pF XOSC,GAIN=1, Cshunt=2.5pF	-	-	240
		F = 8MHz - CL=20 pF XOSC,GAIN=2, Cshunt=5.5pF	-	-	105
		F = 16MHz - CL=20 pF XOSC,GAIN=3, Cshunt=4pF	-	-	60
		F = 32MHz - CL=20 pF XOSC,GAIN=4, Cshunt=3.9pF	-	-	55
Cxin⁽²⁾	Parasitic load capacitor		-	6.7	-	pF
Cxout⁽²⁾	Parasitic load capacitor		-	4.2	-	pF
Tstart⁽²⁾	Startup time	F = 2MHz - CL=20 pF XOSC,GAIN=0, Cshunt=3.3pF	-	15.6K	81.6K	Cycles
		F = 4MHz - CL=20 pF XOSC,GAIN=1, Cshunt=2.5pF	-	6.3K	25.2K
		F = 8MHz - CL=20 pF XOSC,GAIN=2, Cshunt=5.5pF	-	6.2K	27.2K
		F = 16MHz - CL=20 pF XOSC,GAIN=3, Cshunt=4pF	-	7.7K	27.3K
		F = 32MHz - CL=20 pF XOSC,GAIN=4, Cshunt=3.9pF	-	6.0K	21K
CL⁽¹⁾	Crystal load capacitance		10	-	20	pF
Pon⁽¹⁾	Drive Level	AMPGC=ON	-	-	100	uW

Note:

These values are based on simulation. They are not covered by production test limits or characterization.
These values are based on characterization. They are not covered in test limits in production.

Table 46-46. Power Consumption ⁽¹⁾
Symbol	Parameter	Conditions		Ta	Min.	Typ.	Max.	Units
I_DD	Current consumption	F=2MHz - CL=20pF XOSC,GAIN=0, VCC=3.3V	AMPGC=OFF	Max 85°C Typ 25°C	-	66	85	µA
		F=2MHz - CL=20pF XOSC,GAIN=0, VCC=3.3V	AMPGC=ON		-	62	99
		F=4MHz - CL=20pF XOSC,GAIN=1, VCC=3.3V	AMPGC=OFF		-	107	140
		F=4MHz - CL=20pF XOSC,GAIN=1, VCC=3.3V	AMPGC=ON		-	70	101
		F=8MHz - CL=20pF XOSC,GAIN=2, VCC=3.3V	AMPGC=OFF		-	200	261
		F=8MHz - CL=20pF XOSC,GAIN=2, VCC=3.3V	AMPGC=ON		-	118	153
		F=16MHz - CL=20pF XOSC,GAIN=3, VCC=3.3V	AMPGC=OFF		-	436	581
		F=16MHz - CL=20pF XOSC,GAIN=3, VCC=3.3V	AMPGC=ON		-	247	329
		F=32MHz - CL=20pF XOSC,GAIN=4, VCC=3.3V	AMPGC=OFF		-	1303	1902
		F=32MHz - CL=20pF XOSC,GAIN=4, VCC=3.3V	AMPGC=ON		-	627	940

Note:

These values are based on characterization. They are not covered in test limits in production.