6

Linear Equivalent Circuit

In order to predict the performance of the HMPP-3890 as

a switch, it is necessary to construct a model which can

then be used in one of the several linear analysis programs

presently on the market. Such a model is given in Figure

16, where R

in Figure 2. Careful examination of Figure 16 will reveal

the fact that the package parasitics (inductance and ca-

pacitance) are much lower for the MiniPak than they are

for leaded plastic packages such as the SOT-23, SOT-323

or others. This will permit the HMPP-389x family to be

used at higher frequencies than its conventional leaded

counterparts.

APLAC parameter can be obtained at http://www.

hp.woodshot.com/hprfhelp/design/SPICE/pins.

htm#HSMP389x website

Figure 11a. Linear Equivalent Circuit of the MiniPak 1412 PIN Diode.

30 fF

30 fF

20 fF

20 fF

1.1 nH

Single diode package (HMPP-3890)

2

3

1

4

30 fF

30 fF

20 fF

20 fF

12 fF

12 fF

0.5 nH

Anti-parallel diode package (HMPP-3892)

2

3

1

4

0.5 nH

0.05 nH

0.5 nH

0.05 nH

0.05 nH

0.5 nH

0.05 nH

30 fF

30 fF

20 fF

20 fF

0.5 nH

0.05 nH

Parallel diode package (HMPP-3895)

2

3

1

4

0.5 nH

0.05 nH

0.5 nH

0.05 nH

0.5 nH

0.05 nH

30fF

30fF

0.5nH

0.5nH

0.1nH

0.1nH

0.05nH

0.05nH

0.05nH

0.05nH

3

2

4

1

20fF

Diode package (HMPP-389T)

20fF