TDK5111FXT Infineon Technologies, TDK5111FXT Datasheet - Page 22

• Manufacturer Part Number: TDK5111FXT
• Manufacturer: Infineon Technologies

Specifications of TDK5111FXT

• Operating Temperature (min): -40C
• Operating Temperature (max): 125C
• Operating Temperature Classification: Automotive
• Product Depth (mm): 4.4mm
• Operating Supply Voltage (min): 2.1V
• Operating Supply Voltage (typ): 2.5/3.3V
• Lead Free Status / Rohs Status: Compliant

3.4
Application Hints on the crystal oscillator
The crystal oscillator achieves a turn on time in the range of 1 msec depending on the
used crystal. To achieve this, a NIC oscillator type is implemented in the TDK 5111 F.
The input impedance of this oscillator is a negative resistance in series to an inductance.
Therefore the load capacitance of the crystal CL (specified by the crystal supplier) is
transformed to the capacitance Cv.
Figure 11
Formula 1:
CL:
ω:
L:
Example for the ASK-Mode:
Referring to the application circuit, in ASK-Mode the capacitance C2 is replaced by a
short to ground. Assume a crystal frequency of 9.84 MHz and a crystal load capacitance
of CL = 12 pF. The inductance L at 9.84 MHz is about 4.6 µH. Therefore C1 is calculated
to 10 pF.
Data Sheet
crystal load capacitance for nominal frequency
angular frequency
inductance of the crystal oscillator
Application Hints on the Crystal Oscillator
Application Hints
-R
Cv
Cv
=
L
IC
CL
=
1
CL
1
+
22
1
ω
+
1
2
ω
L
f, CL Cv
2
L
=
C
1
V 1.1, 2007-09-18
Applications
TDK5111F