4

Microstrip Series Connection for HSMP-481x Series

In order to take full advantage of the low inductance of the

HSMP-481x series when using them in series applications,

both lead 1 and lead 2 should be connected together, as

shown in Figure 7.

Microstrip Shunt Connections for HSMP-481x Series

In Figure 8, the center conductor of the microstrip

line is interrupted and leads 1 and 2 of the HSMP-481x

series diode are placed across the resulting gap. This forces

the 1.5 nH lead inductance 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 nHof shunt inductance external to the

diode is created by the via holes, and is a good estimate

for 0.032" thick material.

Typical Applications for HSMP-481x Low Inductance Series

12

3

HSMP-481x

Figure 6. Internal Connections.

Figure 7. Circuit Layout.

Figure 8. Circuit Layout.

Figure 9. Equivalent Circuit.

50 OHM MICROSTRIP LINES

PAD CONNECTED TO

GROUND BY TWO

VIA HOLES

0.3 nH

0.3 nH

0.3 pF

Rj

1.5 nH

1.5 nH

R

j

0.08

+ 2.5

I

b

0.9