7 / 10 page
7 of 12
SiW1711
60 0047 R00Grf SiW1711 Radio Modem IC DS
External Reference Requirements
It is possible to provide a number of reference frequencies that are typical on most cellular phones directly into pin 25
(XTAL_P/CLK) of the device. The following reference frequencies (in MHz) can be used: 3.84, 9.6, 12, 12.8, 13, 14.4,
15.36, 16, 16.8, 19.2, 19.68, 19.8, 26, 32, 38.4, and 48 MHz. For other frequencies, please contact applications support.
Crystal Requirements
If using a crystal as the source for the reference frequency, the typical parameters are outlined below. The system clock
crystal should operate in a fundamental, parallel resonant mode.
Parameter
Description
Min
Max
Unit
Phase noise
100 kHz offset
–
-100
dBc/Hz
1 kHz offset
–
-120
dBc/Hz
10 kHz offset
–
-140
dBc/Hz
Drive level
AC coupled amplitude
0.5
VCC
VP-P
DC coupled low peak voltage
0
0.3
V
DC coupled high peak voltage
VCC - 0.3
VCC
V
Parameter
Description
Min
Typ
Max
Units
Drive level
–
0.5
–
2.0
VP-P
ESR
Effective serial resistance1
–
–
150
Ω
CO
Holder capacitance2
–3.0
5.0
pF
CL
Load capacitance2
–
12.0
18.0
pF
CM
Motional capacitance
–
6.0
–
fF
1For 32MHz crystal.
2The actual values for CO and CL are dependent on the crystal manufacturer and can be compensated for by an internal crystal calibra-
tion capability.