TDA5251 Infineon Technologies, TDA5251 Datasheet - Page 39
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TDA5251
Manufacturer Part Number
TDA5251
Description
TXRX FSK/ASK SGL LP TSSOP-38
Manufacturer
Infineon Technologies
Type
Transceiverr
Specifications of TDA5251
Package / Case
38-TSSOP
Frequency
315MHz
Data Rate - Maximum
64kbps
Modulation Or Protocol
ASK, FSK
Applications
RKE, Remote Control Systems
Power - Output
13dBm
Sensitivity
-109dBm
Voltage - Supply
2.1 V ~ 5.5 V
Current - Receiving
9.3mA
Current - Transmitting
14mA
Data Interface
PCB, Surface Mount
Antenna Connector
PCB, Surface Mount
Operating Temperature
-40°C ~ 85°C
Operating Frequency
0.35 MHz
Operating Supply Voltage
2.5 V, 3.3 V, 5 V
Maximum Operating Temperature
+ 85 C
Minimum Operating Temperature
- 40 C
Mounting Style
SMD/SMT
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)
2.1V
Operating Supply Voltage (max)
5.5V
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Memory Size
-
Lead Free Status / Rohs Status
Compliant
Other names
SP000014554
TDA5251
TDA5251INTR
TDA5251XT
TDA5251
TDA5251INTR
TDA5251XT
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
TDA5251
Manufacturer:
INFINEON
Quantity:
276
Measured Magnitude of S11 of evalboard:
Figure 3-3
Above you can see the measured S11 of the evalboard. The –3dB-points are at 288MHz and
344MHz. So the 3dB-bandwidth is:
The loaded Q of the resonant circuit is:
The unloaded Q of the resonant circuit is equal to the Q of the inductor due to its losses.
An approximation of the losses of the input matching network can be made with the formula:
Data Sheet
LOSS
=
B
−
Q
20
=
Q
U
*
U f
L
log
=
=
Q
S11 measured
−
1
INDUCTOR
f
−
f
center
L
Q
Q
B
=
U
L
344
=
=
−
MHz
20
315
≈
56
*
27
log
MHz
−
MHz
@
288
1
315
−
MHz
5
27
=
MHz
6 ,
5
6 ,
=
=
2
56
dB
MHz
39
[3 – 4]
[3 – 1]
[3 – 3]
[3 – 2]
TDA5251 F1
S11_measured_315.pcx.
Version 1.1
Application
2007-02-26