8
Typical Applications for HSMP-48XX Low Inductance Series
3
3
Microstrip Series
Connection for
HSMP-48XB Series
In order to take full advantage of
the low inductance of the
HSMP-48XB series when using
them in series applications, both
lead 1 and lead 2 should be
connected together, as shown in
Figure 21.
1
2
1
2
HSMP-481B
HSMP-489B
Figure 21. Internal Connections.
Figure 22. Circuit Layout.
50 OHM MICROSTRIP LINES
Microstrip Shunt
Connections for
HSMP-48XB Series
In Figure 23, the center conductor
of the microstrip line is inter-
rupted and leads 1 and 2 of the
HSMP-48XB series diode are
placed across the resulting gap.
This forces the 0.5 nH lead induc-
tance of leads 1 and 2 to appear as
part of a low pass filter, reducing
the shunt parasitic inductance and
increasing the maximum available
attenuation. The 0.3 nH of shunt
inductance external to the diode is
created by the via holes, and is a
good estimate for 0.032" thick
material.
PAD CONNECTED TO
GROUND BY TWO
VIA HOLES
Figure 23. Circuit Layout.
1.5 nH
1.5 nH
0.3 pF*
0.3 nH
0.3 nH
*0.8 pF TYPICAL FOR HSMP-482B
Figure 24. Equivalent Circuit.
AGILENT [ AGILENT TECHNOLOGIES, LTD. ]
