HSMS-2863-BLKG Avago Technologies US Inc., HSMS-2863-BLKG Datasheet - Page 12

• Manufacturer Part Number: HSMS-2863-BLKG
• Description: DIODE SCHOTTKY DETECT HF SOT-23
• Manufacturer: Avago Technologies US Inc.

Specifications of HSMS-2863-BLKG

• Diode Type: Schottky - 1 Pair Common Anode
• Package / Case: SOT-23-3, TO-236-3, Micro3™, SSD3, SST3
• Voltage - Peak Reverse (max): 4V
• Capacitance @ Vr, F: 0.3pF @ 0V, 1MHz
• Diode Case Style: SOT-23
• Leaded Process Compatible: Yes
• Peak Reflow Compatible (260 C): Yes
• Mounting Type: Surface Mount
• Current Rating: 1A
• Diode Configuration: Dual Common Anode
• Forward Current If Max: 1mA
• Capacitance Ct: 0.3pF
• No. Of Pins: 3
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Max: -
• Power Dissipation (max): -
• Resistance @ If, F: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

The line marked “RF diode, V
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, demonstrating
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
sites on the wafer. A similar circuit can be realized using
the HSMS‑286R ring quad.
Other configurations of six lead Schottky products can
be used to solve circuit design problems while saving
space and cost.
Thermal Considerations
The obvious advantage of the SOT‑363 over the SOT‑
143 is combination of smaller size and two extra leads.
However, the copper leadframe in the SOT‑323 and SOT‑
363 has a thermal conductivity four times higher than
the Alloy 42 leadframe of the SOT‑23 and SOT‑143, which
enables it to dissipate more power.
The maximum junction temperature for these three
families of Schottky diodes is 150°C under all operating
conditions. The following equation, equation 1, applies
to the thermal analysis of diodes:
where
12
I
f
T
θ
= I
T
T
θ
V
jc
j
a
j
f
jc
= (V
= junction temperature
= θ
I
= diode case temperature
S
f
= thermal resistance
f
matching
= DC power dissipated
network
characteristics, because they came from adjacent
e
pkg
f
11600 (V
I
f
+ θ
+ P
chip
RF
nT
) θ
f
bias
- I
jc
+ T
f
R
s
a
)
- 1
out
” is the transfer curve for
differential
amplifier
Equation (1).
Equation (2).
Equation (3).
Note that θ
to the foot of the leads, is the sum of two component
resistances,
Package thermal resistance for the SOT‑323 and SOT‑363
package is approximately 100°C/W, and the chip thermal
resistance for these three families of diodes is approxi‑
mately 40°C/W. The designer will have to add in the
thermal resistance from diode case to ambient — a poor
choice of circuit board material or heat sink design can
make this number very high.
Equation (1) would be straightforward to solve but
for the fact that diode forward voltage is a function of
temperature as well as forward current. The equation,
equation 3, for V
where
and I
Equations (1) and (3) are solved simultaneously to obtain
the value of junction temperature for given values of
diode case temperature, DC power dissipation and RF
power dissipation.
I
I
I
I
I
I
f
s
f
f
s
s
T
θ
T
θ
T
θ
= I
= I
= I
= I
= I
= I
P
n = ideality factor
T = temperature in °K
R
jc
jc
jc
j
j
j
RF
s
= (V
= (V
= (V
S
= θ
= θ
= θ
S
0
S
S
0
0
= diode series resistance
= RF power dissipated
(diode saturation current) is given by
(
(
(
e
e
e
pkg
pkg
pkg
298
298
298
f
f
f
11600 (V
11600 (V
11600 (V
T
T
T
I
I
I
f
f
f
jc
+ θ
+ θ
+ θ
+ P
+ P
+ P
, the thermal resistance from diode junction
)
)
)
2
n - 4060
2
n - 4060
2
n - 4060
chip
chip
chip
RF
RF
RF
e
e
e
f
nT
nT
nT
is:
) θ
) θ
) θ
f
f
f
- I
- I
- I
jc
jc
jc
+ T
+ T
+ T
f
f
f
R
R
R
(
(
(
s
s
s
1
1
1
a
a
a
)
T
)
)
T
T
- 1
- 1
- 1
-
-
-
1
298
1
298
1
298
)
)
)
Equation (1).
Equation (2).
Equation (1).
Equation (2).
Equation (1).
Equation (2).
Equation (3).
Equation (4).
Equation (3).
Equation (3).
Equation (4).
Equation (4).