HFA3101BZ Intersil, HFA3101BZ Datasheet - Page 7

• Manufacturer Part Number: HFA3101BZ
• Description: IC TRANSISTOR ARRAY UHF 8-SOIC
• Manufacturer: Intersil

Specifications of HFA3101BZ

• Frequency: 0Hz ~ 10GHz
• Number Of Mixers: 1
• Noise Figure: 1.7dB
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Voltage - Supply: -
• Rf Type: -
• Gain: -
• Secondary Attributes: -

of the circuit upon higher level signals. The drop across R
must be taken into consideration when setting the current
source value.
Figure 3B depicts the use of a common resistor sharing the
current through the cell which is used for temperature
Design Example: Down Converter Mixer
Figure 4 shows an example of a low cost mixer for cellular
applications.
R
0.01
0.01
0.01
LO IN
BIAS
R
2
825MHz
V
FIGURE 4. 3V DOWN CONVERTER APPLICATION
CC
R
0.01
1
110
330
220
V
Q
R
R
R
CC
B1
1
EE
FIGURE 3A.
B2
Q
Q
51
5
2
Q
Q
R
Q
1
E
3
R
6
Q
EE
Q
Q
5
2
4
3-7
L
CH
27
Q
Q
3
6
Q
4
390nH
L
CH
51
R
5p TO 12p
2K
BIAS
0.01
R
2
R
0.1
900MHz
IF OUT
75MHz
RF IN
1
V
CC
EE
R
Q
3V
R
R
HFA3101
B1
1
EE
FIGURE 3B.
B2
FIGURE 3.
Q
Q
5
2
Q
R
Q
3
E
R
6
compensation as the lower pair V
-2mV/
Figure 3C uses a split supply.
The design flexibility of the HFA3101 is demonstrated by a
low cost, and low voltage mixer application at the 900MHz
range. The choice of good quality chip components with their
self resonance outside the boundaries of the application are
important. The design has been optimized to accommodate
the evaluation of the same layout for various quiescent
current values and lower supply voltages. The choice of R
became important for the available overhead and also for
maintaining an AC true impedance for high frequency
signals. The value of 27Ω has been found to be the optimum
minimum for the application. The input impedances of the
HFA3101 base input ports are high enough to permit their
termination with 50Ω resistors. Notice the AC termination by
decoupling the bias circuit through good quality capacitors.
The choice of the bias has been related to the available
power supply voltage with the values of R
splitting the voltages for optimum V
of the cell quiescent currents, the voltage at the emitter
resistor R
The gain of the circuit, being a function of the load and the
combined emitter resistances at high frequencies have been
kept to a maximum by the use of an output match network.
The high output impedance of the HFA3101 permits
EE
Q
4
L
CH
R
o
C
C.
E
has been recorded.
V
CC
R
BIAS
R
2
R
1
FIGURE 3C.
BE
Q
R
V
R
R
CE
B1
1
CC
EE
B2
Q
drop at the rate of
Q
5
values. For evaluation
2
V
EE
1
R
, R
Q
Q
E
3
R
6
2
EE
Q
and R
4
L
CH
BIAS
E