TDK5101F_07 INFINEON [Infineon Technologies AG], TDK5101F_07 Datasheet - Page 27

• Manufacturer Part Number: TDK5101F_07
• Description: 315 MHz ASK/FSK Transmitter in 10-pin Package
• Manufacturer: INFINEON [Infineon Technologies AG]

Example for the FSK-Mode:
FSK modulation is achieved by switching the load capacitance of the crystal as shown
below.
Figure 15
The frequency deviation of the crystal oscillator is multiplied with the divider factor N of
the Phase Locked Loop to the output of the power amplifier. In case of small frequency
deviations (up to +/- 1000 ppm), the two desired load capacitances can be calculated
with the formula below.
C
C
f:
ω:
N:
df:
Because of the inductive part of the TDK 5101 F, these values must be corrected by
Formula 1 on the preceding page. The value of Cv± can be calculated.
Data Sheet
L
0
:
:
crystal load capacitance for nominal frequency
shunt capacitance of the crystal
frequency
ω = 2
division ratio of the PLL
peak frequency deviation
FSK Mode
π
f: angular frequency
-R
CL
FSKDTA
Csw
±
=
L
IC
CL
1
m
±
C
N
0
FSKOUT
COSC
∆
*
N
f
f
∆
*
27
1
f
1 (
f
1
+
1 (
f, CL Cv1
( 2
+
C
( 2
0
C
C
+
1
0
C
CL
+
1
CL
)
)
)
)
Cv2
V 1.3, 2007-09-19
Applications
TDK5101F