TDA5250 Infineon Technologies, TDA5250 Datasheet - Page 52

• Manufacturer Part Number: TDA5250
• Description: TX/RX ASK/FSK 868-870MHZ 38TSSOP
• Manufacturer: Infineon Technologies
• Type: Transceiverr

Specifications of TDA5250

• Package / Case: 38-TSSOP
• Frequency: 868MHz
• Data Rate - Maximum: 64kbps
• Modulation Or Protocol: ASK, FSK
• Applications: RKE, Remote Control Systems
• Power - Output: 9dBm
• Sensitivity: -109dBm
• Voltage - Supply: 2.1 V ~ 5.5 V
• Current - Receiving: 9mA
• Current - Transmitting: 12mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Operating Frequency: 870 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: SP000012956; TDA5250; TDA5250INTR; TDA5250XT; TDA5250XT

Figure 3-15
With the aid of this formula it becomes obvious that the higher the serial capacitance C V is, the
higher is the influence of L OSC .
The tolerance of the internal oscillator inductivity is much higher, so the inductivity is the dominating
value for the tolerance.
FSK modulation and tuning are achieved by a variation of C
In case of small frequency deviations (up to +/- 1000 ppm), the desired load capacitances for FSK
modulation are frequency depending and can be calculated with the formula below.
Data Sheet
C
L
=
C L ±
C
1
V
−
Crystal Oscillator
ω
1
=
2
L
C
----------------------------------------------------------------------------------------- -
OSC
C
ω:
L
C
C
C
f:
N:
L
OSC
1
L
L
0
1
+ −
:
:
:
:
±
↔
C
----------
N f ⋅
0
:
∆f
C
⋅
----------
N f ⋅
V
∆f
-R
⋅
=



crystal load capacitance for nominal frequency
angular frequency
inductivity of the crystal oscillator - typ: 2.7µH with pad of board
crystal load capacitance for nominal frequency
shunt capacitance of the crystal
motional capacitance of the crystal
crystal oscillator frequency
division ratio of the PLL
1
C
⋅
1
+



L
1
2
---------------------------------
+
+
⋅
ω
1
(
2
---------------------------------
C
2
TDA 5250
⋅
C
0
L
(
1
L
OSC
C
+
OSC
C 1
0
C
+
L
C
)



L
)
52



f, C
v
.
L
C
2.45µH without pad
V
[3 – 18]
[3 – 17]
TDA5250 D2
Version 1.7
Application
2007-02-26
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