HSMS-286C-TR1 Avago Technologies US Inc., HSMS-286C-TR1 Datasheet - Page 11

• Manufacturer Part Number: HSMS-286C-TR1
• Description: DETECTOR DIODE,SOT-323
• Manufacturer: Avago Technologies US Inc.

Specifications of HSMS-286C-TR1

• Rohs Compliant: NO
• Diode Type: Schottky - 1 Pair Series Connection
• Voltage - Peak Reverse (max): 4V
• Capacitance @ Vr, F: 0.25pF @ 0V, 1MHz
• Package / Case: SC-70-3, SOT-323-3
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Max: -
• Power Dissipation (max): -
• Resistance @ If, F: -
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Six Lead Circuits
The differential detector is often
used to provide temperature
compensation for a Schottky
detector, as shown in Figures 27
and 28.
Figure 27. Differential Detector.
Figure 28. Conventional Differential
Detector.
These circuits depend upon the
use of two diodes having matched
V
operating temperatures. This is
best achieved by using two
diodes in a single package, such
as the SOT-143 HSMS-2865 as
shown in Figure 29.
In high power differential detec-
tors, RF coupling from the
detector diode to the reference
diode produces a rectified voltage
in the latter, resulting in errors.
Isolation between the two diodes
can be obtained by using the
HSMS-286K diode with leads 2
and 5 grounded. The difference
between this product and the
conventional HSMS-2865 can be
seen in Figure 29.
f
PA
characteristics over all
matching
network
HSMS-2865
bias
detector
diode
reference diode
differential
V
amplifier
s
to differential
amplifier
Figure 29. Comparing Two Diodes.
The HSMS-286K, with leads 2 and
5 grounded, offers some isolation
from RF coupling between the
diodes. This product is used in a
differential detector as shown in
Figure 30.
Figure 30. High Isolation
Differential Detector.
In order to achieve the maximum
isolation, the designer must take
care to minimize the distance
from leads 2 and 5 and their
respective ground via holes.
Tests were run on the HSMS-282K
and the conventional HSMS-2825
pair, which compare with each
other in the same way as the
HSMS-2865 and HSMS-286K, with
the results shown in Figure 31.
Figure 31. Comparing HSMS-282K
with HSMS-2825.
PA
5000
1000
3
100
0.5
10
1
1
-35
HSMS-2865
Frequency = 900 MHz
SOT-143
Square law
response
-25
INPUT POWER (dBm)
HSMS-286K
4
2
-15
37 dB
47 dB
detector
diode
-5
reference diode
RF diode
HSMS-2825
ref. diode
V
6
1
out
HSMS-286K
V
s
SOT-363
5
2
5
HSMS-282K
ref. diode
to differential
15
4
amplifier
3
The line marked “RF diode, V
is the transfer curve for the
detector diode — both the
HSMS-2825 and the HSMS-282K
exhibited the same output
voltage. The data were taken over
the 50 dB dynamic range shown.
To the right is the output voltage
(transfer) curve for the reference
diode of the HSMS-2825, showing
37 dB of isolation. To the right of
that is the output voltage due to
RF leakage for the reference
diode of the HSMS-282K, demon-
strating 10 dB higher isolation
than the conventional part.
Such differential detector circuits
generally use single diode
detectors, either series or shunt
mounted diodes. The voltage
doubler offers the advantage of
twice the output voltage for a
given input power. The two
concepts can be combined into
the differential voltage doubler,
as shown in Figure 32.
Figure 32. Differential Voltage
Doubler, HSMS-286P.
Here, all four diodes of the
HSMS-286P are matched in their
V
came from adjacent sites on the
wafer. A similar circuit can be
realized using the HSMS-286R
ring quad.
f
matching
network
characteristics, because they
11
bias
differential
amplifier
out
”