TDK5110FHTMA1 Infineon, TDK5110FHTMA1 Datasheet - Page 32

• Manufacturer Part Number: TDK5110FHTMA1
• Description: Transmitter Ask/Fsk Sgl Tssop10
• Manufacturer: Infineon

Wireless Components
As Figure 4-10 shows, detuning beyond the bandwidth of the matching circuit
results in an increase of the collector current of the power amplifier and in some
loss of output power. This diagram shows the data for the circuit of the test
board at the frequency of 434 MHz. The behaviour at 868 MHz is similar. The
effective load resistance of this circuit is R
impedance for operation at 3 V. This will lead to a dip of the collector current of
approx. 10%.
Figure 4-10
C3, L2-C2 and C8 are the main matching components which are used to
transform the 50
PA-output (250
frequency but should not become too small in order to keep its losses low.
The transformed impedance of 250+j0
with a network analyzer using the following measurement procedure:
1. Calibrate your network analyzer.
2. Connect some short, low-loss 50
3. Use the „Port Extension“ feature of your network analyzer to shift the refer-
4. Connect the center-conductor of the cable to the solder pad of the pin „PA“
5. Screw a 50
6. Be sure that your network analyzer is AC-coupled and turn on the power
7. Measure the S-parameter S11
open end on one side. Semirigid cable works best.
ence plane of your network analyzer to the open end of the cable.
of the IC. The outer conductor has to be grounded. Very short connections
have to be used. Do not remove the IC or any part of the matching-compo-
nents!
supply of the IC. The TDK5110 has to be in PLL-Enable-Mode.
1 6
1 4
1 2
1 0
8
6
4
2
0
3 7 5
Output power and collector current vs. frequency
dummy-load on the RF-I/O-SMA-connector
4 0 0
@ 3 V). L1 can be used for some finetuning of the resonant
load at the SMA-RF-connector to a higher impedance at the
4 - 12
4 2 5
f [ M H z ]
4 5 0
cable to your network analyzer with an
at the PA-output-pin can be verified
L
= 250
4 7 5
Specification, October 2002
, which is the optimum
5 0 0
4 3 4 M H z / 3 V
T D K 5 1 1 0
Is [m A ]
P o u t [ d B m ]
Applications
TDK 5110
pout_vs_frequ.wmf