HMPP-3892 Datasheet, PDF (8/12 Pages) Broadcom Corporation. – MiniPak Surface Mount RF PIN Switch Diodes

Insertion loss of the reference was very low and generally,
increased with frequency (Figure 21). If the demo-board
has been constructed carefully, there should not be any
evidence of resonance. The reference line’s ­insertion loss
trace can be stored in the VNA’s display memory and
used to correct for the insertion loss of the test line in the
subsequent measurements.
0
-0.2
-0.4
-0.6
0
-0.2
-0.4
-0.6
-0.8
-1.0
1
2
3
4
5
6
FREQUENCY (GHz)
Figure 18. Insertion Loss of HMPP-389T at
Figure 18. In₀s_Ve_.rtion loss of HMPP-389T at 0V.
-0.8
0
-1.0
-0.2
1
2
3
4
5
6
FREQUENCY (GHz)
-0.4
Figure 16. Insertion Loss of Reference
Figure 16. In_Ls_ine_ert_.ion loss of reference line.
-0.6
To evaluate the HMPP-389T as shunt switch, it was
mounted on the test line and then the appropriate bias-
ing voltage was applied. In our prototype, the worst case
return loss was 10 dB at 5 GHz (Figure 22). The return loss
varied very little when the bias was changed from zero
to -20V.
-5
-15
-25
-35
-45
-55
1
2
3
4
5
6
FREQUENCY (GHz)
Figure 17. Return Loss of HMPP-389T
Figure 18. R^Me^oturⁿn^tel^dos^osⁿof^TeH^sM^t P^LPⁱⁿ-3^e8^a9^tT⁰m^V o^auⁿn^dt^-e²d^0Von^Bt^iae^st^. line at 0V and -20V
bias.
Normalization was used to remove the pcb’s and connec-
tors’ losses from the measurement of the shunt switch’s
loss. The active trace was divided by the memorized
trace (Data/Memory) to produce the normalized data.
At zero bias, the insertion loss was under 0.6 dB up to 6
GHz (Figure 23). Applying a reverse bias to the PIN diode
has the effect of reducing its parasitic ­capacitance. With a
reverse bias of -20V, the insertion loss improved to better
than 0.5 dB (Figure 24).
-0.8
-1.0
1
2
3
4
5
6
FREQUENCY (GHz)
Figure 19. In^Fsⁱe^gr^ut^ri^eon¹⁹lo^. s^Isⁿo^sf^eH^rtM^ioPⁿP^L-3^o8^s9^sT^oa^ft^H-^M20^PV^P. ^{-389T at}
-20V.
The PIN diode’s resistance is a function of the bias ­current.
So, at higher forward current, the isolation ­ improved.
The combination of the HMPP-389T and the SK063A
demoboard exhibited more than 17 dB of isolation from
1 to 6 GHz at If ≥ 1mA (Figure 25).
-10
0.15 mA
-14 ^{0.25 mA}
0.5 mA
-18 1 mA
-22 ^{1.5 mA}
-26
20 mA
-30
1
2
3
4
5
6
FREQUENCY (GHz)
Figure 20.
parameter.
Fw_Isiig_othularF_te_ioo2r_nw0.aarItsdo_dClia_fuft_eriorrenennat_ttaD_fsri_eaffqeP_ura_eer_nnat_cmiF_eerseteq_wru.ite_hnc_fi_oe_rs_ward
current
as
a
The combination of the HMPP‑389T and the demo-board
allows a high performance shunt switch to be constructed
swiftly and economically. The extremely low parasitic
inductance of the package allows the switch to operate
over a very wide frequency range.