Specifications

CC1101
SWRS061I Page 18 of 98
4.4 Crystal Oscillator
T
A
= 25C, VDD = 3.0 V if nothing else is stated. All measurement results obtained using the CC1101EM reference designs ([1]
and [2]).
Table 13: Crystal Oscillator Parameters
4.5 Low Power RC Oscillator
T
A
= 25C, VDD = 3.0 V if nothing else is stated. All measurement results obtained using the CC1101EM reference designs ([1]
and [2]).
Table 14: RC Oscillator Parameters
Parameter
Min
Typ
Max
Unit
Condition/Note
Crystal frequency
26
26
27
MHz
For compliance with modulation bandwidth requirements under
EN 300 220 in the 863 to 870 MHz frequency range it is
recommended to use a 26 MHz crystal for frequencies below
869 MHz and a 27 MHz crystal for frequencies above 869 MHz.
Tolerance
±40
ppm
This is the total tolerance including a) initial tolerance, b) crystal
loading, c) aging, and d) temperature dependence. The
acceptable crystal tolerance depends on RF frequency and
channel spacing / bandwidth.
Load capacitance
10
13
20
pF
Simulated over operating conditions
ESR
100

Start-up time
150
µs
This parameter is to a large degree crystal dependent. Measured
on the CC1101EM reference designs ([1] and [2]) using crystal
AT-41CD2 from NDK
Parameter
Min
Typ
Max
Unit
Condition/Note
Calibrated frequency
34.7
34.7
36
kHz
Calibrated RC Oscillator frequency is XTAL
frequency divided by 750
Frequency accuracy after
calibration
±1
%
Temperature coefficient
+0.5
% / C
Frequency drift when temperature changes after
calibration
Supply voltage coefficient
+3
% / V
Frequency drift when supply voltage changes after
calibration
Initial calibration time
2
ms
When the RC Oscillator is enabled, calibration is
continuously done in the background as long as
the crystal oscillator is running