TDA5212XT Infineon Technologies, TDA5212XT Datasheet - Page 30

• Manufacturer Part Number: TDA5212XT
• Manufacturer: Infineon Technologies

Specifications of TDA5212XT

• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 4.4mm
• Product Length (mm): 9.7mm
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / Rohs Status: Compliant

TDA 5212
Applications
gain for the DC content of FSK signal remains at 200µV/kHz. The cutoff fre-
quencies of the bandpass have to be chosen such that the spectrum of the data
signal is influenced in an acceptable amount.
In case that the user data is containing long sequences of logical zeros the
effect of the drift-off of the bit slicer threshold voltage can be lowered if the offset
voltage inherent at the negative input of the slicer comparator (Pin20) is used.
The comparator has no hysteresis built in.
This offset voltage is generated by the bias current of the negative input of the
comparator (i.e. 20nA) running over the external resistor R. This voltage raises
the voltage appearing at pin 20 (e.g. 1mV with R = 100k Ω ). In order to obtain
benefit of this asymmetrical offset for the demodulation of long zeros the lower
of the two FSK frequencies should be chosen in the transmitter as the zero-
symbol frequency.
In the following figure the shape of the above mentioned bandpass is shown.
gain (pin19)
v
v-3dB
20dB/dec
-40dB/dec
3dB
0dB
f
DC
f1
f2
f3
0.18m V/kHz
2mV/k Hz
frequenzgang.WMF
Figure 4-8
Frequency characterstic in case of FSK mode
The cutoff frequencies are calculated with the following formulas:
1
=
f
⋅
Ω
1
R
330
k
π
×
2
C
+
Ω
R
330
k
Wireless Components
4 - 9
Specification, December 2006