HSMS-286C-TR1 Avago Technologies US Inc., HSMS-286C-TR1 Datasheet - Page 6

• 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

N-TYPE OR P-TYPE SILICON SUBSTRATE
N-TYPE OR P-TYPE EPI
PASSIVATION
CROSS-SECTION OF SCHOTTKY
Applications Information
Introduction
Agilent’s HSMS-286x family of
Schottky detector diodes has been
developed specifically for low
cost, high volume designs in two
kinds of applications. In small
signal detector applications
(P
with DC bias at frequencies above
1.5 GHz. At lower frequencies, the
zero bias HSMS-285x family
should be considered.
In large signal power or gain
control applications
(P
without bias at frequencies above
4 GHz. At lower frequencies, the
HSMS-282x family is preferred.
Schottky Barrier Diode
Characteristics
Stripped of its package, a
Schottky barrier diode chip
consists of a metal-semiconductor
barrier formed by deposition of a
metal layer on a semiconductor.
The most common of several
different types, the passivated
diode, is shown in Figure 7, along
with its equivalent circuit.
Figure 7. Schottky Diode Chip.
R
resistance of the diode, the sum of
the bondwire and leadframe
resistance, the resistance of the
bulk layer of silicon, etc. RF
energy coupled into R
heat — it does not contribute to
S
in
in
BARRIER DIODE CHIP
is the parasitic series
> -20 dBm), this family is used
< -20 dBm), this diode is used
METAL
SCHOTTKY JUNCTION
LAYER
PASSIVATION
S
is lost as
EQUIVALENT
C
j
R
CIRCUIT
S
R
j
the rectified output of the diode.
C
tance of the diode, controlled by
the thickness of the epitaxial layer
and the diameter of the Schottky
contact. R
resistance of the diode, a function
of the total current flowing
through it.
where
I
height, and can range from
picoamps for high barrier diodes
to as much as 5 µA for very low
barrier diodes.
The Height of the Schottky
Barrier
The current-voltage characteristic
of a Schottky barrier diode at
room temperature is described by
the following equation:
On a semi-log plot (as shown in
the Agilent catalog) the current
graph will be a straight line with
inverse slope 2.3 X 0.026 = 0.060
volts per cycle (until the effect of
R
at high current). All Schottky
diode curves have the same slope,
but not necessarily the same value
of current for a given voltage. This
S
J
S
n = ideality factor (see table of
T = temperature in °K
I
I
is a function of diode barrier
is parasitic junction capaci-
S
b
is seen in a curve that droops
R
= saturation current (see
= externally applied bias
I = I
j
SPICE parameters)
table of SPICE parameters)
current in amps
= –––––––––––– = R
= ––––– at 25°C
S
8.33 X 10
0.026
I
S
j
(exp
+ I
is the junction
I
S
b
+ I
(
––––––
V - IR
-5
b
0.026
n T
S
)
- 1)
V
– R
s
is determined by the saturation
current, I
barrier height of the diode.
Through the choice of p-type or
n-type silicon, and the selection of
metal, one can tailor the
characteristics of a Schottky
diode. Barrier height will be
altered, and at the same time C
and R
general, very low barrier height
diodes (with high values of I
suitable for zero bias applica-
tions) are realized on p-type
silicon. Such diodes suffer from
higher values of R
n-type. Thus, p-type diodes are
generally reserved for small signal
detector applications (where very
high values of R
R
mixer applications (where high
L.O. drive levels keep R
DC biased detectors.
Measuring Diode Linear
Parameters
The measurement of the many
elements which make up the
equivalent circuit for a packaged
Schottky diode is a complex task.
Various techniques are used for
each element. The task begins
with the elements of the diode
chip itself. (See Figure 8).
Figure 8. Equivalent Circuit of a
Schottky Diode Chip.
R
measure accurately. The V-I curve
is measured for the diode under
forward bias, and the slope of the
curve is taken at some relatively
S
S
) and n-type diodes are used for
is perhaps the easiest to
6
R
S
S
will be changed. In
S
, and is related to the
R
V
V
C
j
swamp out high
S
than do the
V
low) and
S
,
J