isl55016 Intersil Corporation, isl55016 Datasheet - Page 9

• Manufacturer Part Number: isl55016
• Description: Mmic Silicon Bipolar Differential Amplifier
• Manufacturer: Intersil Corporation

Trade-off Between Power and OIP2
The values of R
and 0Ω. Decreasing the R
voltage across the output transistor leading to an increase in
the dissipation power. At the same time, it will increase the
amplitude of the compression, OIP2 and OIP3. Figures 21, 22
and 26 show this effect on OIP2. Figure 25 shows the
compression point changed with different resistors. Figure 28
shows the OIP3 changed with different resistors. One needs
to trade-off between the power dissipation and higher OIP2.
RF IN
RF IN
1
and R
FIGURE 30. COMPARISON OF ISL55012 WITH A BALUN AND ISL55016 (RELATIVE SIZE)
2
C
(Figure 29) have two options; 27Ω
1
and R
ISL55012
C
C
9
GND
ISL55016
RF IN
2
value will increase the
C
VDD
VDD
C
GND
FIGURE 31. PCB LAYOUT OF MATCHING NETWORK
L
L
L
75
C
R
C
C1
Ω
C
50
R
R
Ω
L
C
100
VDD
Ω
VDD
C2
ISL55016
L
C
DIFFERENTIAL
OUT
VDD
C3
Matching at the Input and Output
In the PCB Layout Design, a matching network is needed,
especially at the input. Figure 31 shows the matching
network used for the ISL55016 Evaluation Board. 12mm
100Ω trace and 6mm 50Ω trace are used to form the input
matching network and 4mm 100Ω trace to form the output
matching network on the FR4 material.
In Figure 31, the S11 is improved at 2GHz with the matching
network, to less than -10dB.
C
C
100
100
50
L1
L2
Ω
Ω
Ω
50
Ω
RF OUT
RF OUT
BALUN
C
DIFFERENTIAL
C
OUT
June 24, 2008
FN6526.1