TDA7210 Infineon Technologies, TDA7210 Datasheet - Page 29

• Manufacturer Part Number: TDA7210
• Description: IC RECEIVER FSK/ASK 28-TSSOP
• Manufacturer: Infineon Technologies
• Type: ASK/FSK Single Conversion Receiverr

Specifications of TDA7210

• Package / Case: 28-TSSOP
• Frequency: 810MHz ~ 870MHz, 400MHz ~ 440MHz
• Sensitivity: -110dBm
• Data Rate - Maximum: 100 kbps
• Modulation Or Protocol: ASK, FSK
• Applications: Remote Control, RKE, Security Systems
• Current - Receiving: 5.9mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Supply Current: 7.7 mA
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4.5 V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (max): 5.5V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 28
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant
• Other names: SP000524274; TDA7210; TDA7210INTR

Wireless Components
4.6.1
4.6 ASK/FSK Switch Functional Description
The TDA7210 is containing an ASK/FSK switch which can be controlled via
Pin 15 (MSEL). This switch is actually consisting of 2 operational amplifiers that
are having a gain of 1 in case of the ASK amplifier and a gain of 11 in case of
the FSK amplifier in order to achieve an appropriate demodulation gain charac-
teristic. In order to compensate for the DC-offset generated especially in case
of the FSK PLL demodulator there is a feedback connection between the
threshold voltage of the bit slicer comparator (Pin 20) to the negative input of
the FSK switch amplifier. This is shown in the following figure.
Figure 4-7
FSK Mode
The FSK datapath has a bandpass characterisitc due to the feedback shown
above (highpass) and the data filter (lowpass). The lower cutoff frequency f2 is
determined by the external RC-combination. The upper cutoff frequency f3 is
determined by the data filter bandwidth.
The demodulation gain of the FSK PLL demodulator is 200µV/kHz. This gain is
increased by the gain v of the FSK switch, which is 11. Therefore the resulting
dynamic gain of this circuit is 2.2mV/kHz within the bandpass. The gain for the
DC content of FSK signal remains at 200µV/kHz. The cutoff frequencies of the
bandpass have to be chosen such that the spectrum of the data signal is influ-
enced in an acceptable amount.
In case that the user data is containing long sequences of logical zeroes 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.
1.5 V......2.5 V
0.2 mV/kHz
typ. 2 V
FSK PLL Demodulator
ASK/FSK mode datapath
RSSI (ASK signal)
ASK mode : v=1
FSK mode : v=11
R
-
+
+
-
30k
F4 int
4 - 8
ASK
FSK
15
R
300k
ASK/FSK Switch
F3 int
MSEL
R
100k
FFB
F1 int
22
R
100k
C
F2 int
Data Filter
12
21
OPP
v = 1
C
14
SLP
Data Sheet, December 2008
19
R
1
20
+
-
C
SLN
13
Comp
Applications
ask_fsk_datapath.WMF
TDA7210
DATA Out
25