HMC521ALC4 Data Sheet
Rev. 0 | Page 22 of 24
APPLICATIONS INFORMATION
TYPICAL APPLICATION CIRCUIT
Figure 86 shows the typical application circuit for the
HMC521ALC4. The HMC521ALC4 is a passive device and
does not require any external components. The LO and RF pins
are internally ac-coupled. The IFx pins are internally dc-coupled.
For applications not requiring operation to dc, dc block this
port externally using a series capacitor of a value chosen to pass
the necessary IF frequency range. When IF operation to dc is
required, do not exceed the IFx source and sink current rating
specified in the Absolute Maximum Ratings section. To select
the upper sideband when using the HMC521ALC4 as an
upconverter, connect the IF1 pin to the 90° port of the hybrid,
and connect the IF2 pin to the 0° port of the hybrid. To select
the lower sideband, connect the IF1 pin to the 0° port of the
hybrid and the IF2 pin to the 90° port of the hybrid. The input
is from the sum port of the hybrid, and the difference port is
50 Ω terminated.
To select the upper sideband (low-side LO) when using as
downconverter, connect the IF1 pin to the 0° port of the hybrid,
and connect the IF2 pin to the 90° port of the hybrid. To select
the lower sideband (high-side LO), connect the IF1 pin to the
90° port of the hybrid and connect the IF2 pin to the 0° port of
the hybrid. The output is from the sum port of the hybrid, and
the difference port is 50 Ω terminated.
PACKAGE
BASE
RF
IF1 IF2
LO
90°
HYBRID
50Ω IF
SUPPLY
FOR IF1
SUPPLY
FOR IF2
BIAS TEE/
DC FEED FOR IF2
BIAS TEE/
DC FEED FOR IF1
DC BLOCKING
CAPACITORS
EXTERNAL
90° HYBRID
NOTES
1. DASHED SECTIONS ARE OPTIONAL AND MEANT FOR LO NULLING.
13
1
3
4
2
7
5
6
14
15
16
17
18
8
9
1
0
1
1
1
2
1
9
2
0
2
1
2
2
2
3
2
4
16780-157
Figure 86. Typical Application Circuit
