5

Typical Applications for HSMP-481x Low Inductance Series (continued)

Figure 10. Circuit Layout.

Co-Planar Waveguide

Groundplane

Center Conductor

Groundplane

Co-Planar Waveguide

Shunt Connection for

HSMP-481x Series

Co-Planar waveguide, with

ground on the top side of the

printed circuit board, is shown

in Figure 10. Since it eliminates

the need for via holes to ground,

it offers lower shunt parasitic

inductance and higher maximum

attenuation when compared to a

microstrip circuit.

Figure 11. Equivalent Circuit.

0.3 pF

0.75 nH

0.18 pF*

* Measured at -20 V

2.5

Ω

80 Ω

I

0.9

I = Forward Bias Current in mA

*See AN1124 for package models.

Equivalent Circuit Model

HSMS-381x Chip*