CMOSTEK CMT2300A - Crystal Oscillator Characteristics; Low Frequency Oscillator Specifications

CMT2300A
Rev 1.0 | Page9/46
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Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
MHz
100 kHz frequency deviation
95
dBc/Hz
500 kHz frequency deviation
-114
dBc/Hz
1MHz frequency deviation
-121
dBc/Hz
10 MHz frequency deviation
-130
dBc/Hz
Phase noise@ 915
MHz
PN
915
10 kHz frequency deviation
-89
dBc/Hz
100 kHz frequency deviation
-92
dBc/Hz
500 kHz frequency deviation
-111
dBc/Hz
1MHz frequency deviation
-121
dBc/Hz
10 MHz frequency deviation
-130
dBc/Hz
1.8 Crystal Oscillator
Table 8. Crystal Oscillator Specifications
Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
Crystal frequency
[1]
F
XTAL
26
MHz
Frequency tolerance
[2]
ppm
20
ppm
Load capacitance
C
LOAD
15
pF
Equivalent resistance
Rm
60
Ω
Start-up time
[3]
t
XTAL
400
us
Remarks:
[1]. CMT2300A can use the external reference clock to drive the XIN pin through the coupling capacitor. The peak value of
the external clock signal is between 0.3V and 0.7V.
[2]. The value includes (1) initial error; (2) crystal load; (3) aging; and (4) change with temperature. The acceptable crystal
frequency tolerance is limited by the receiver bandwidth and the RF frequency offset between the transmitter and the
receiver.
[3]. The parameter is largely related to the crystal.
1.9 Low Frequency Oscillator
Table 9. Low Frequency Oscillator Specifications
Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
Calibration frequency
[1]
F
LPOSC
32
kHz
Frequency accuracy
After calibration
±1
%
Temperature coefficient
[2]
-0.02
%/°C
Supply voltage coefficient
[3]
+0.5
%/V
Initial calibration time
t
LPOSC-CAL
4
ms
Remarks:
[1]. The low frequency oscillator is automatically calibrated to the crystal oscillator frequency at the PUP stage and
periodically calibrated at this stage.
[2]. After calibration, the frequency changes with temperature.
[3]. After calibration, the frequency changes with the change of the supply voltage.