Advertisement
0\
:Pag(,5
.,.
. ..
~~
..
~
"'
..
,.-.,~.,
..
~
--
..
~.-
,
r-
.•...••.
~
h~_··
.. " _.. · ' M __··
~
__
_.__
,
" , I,
~
.'
"
.
"'.
,
,
I.
" ! )
i
_..
-,._-~-
.._---
._.-,,~-_..:..~-l\----
-"---"--'--'-
Figure, 5.. Typical Frequency Response
'\
. 70 .._--. . _...._ ......_ ....--..
1-·..;·.. · ......_-··..··..
·1
,
'.
"
,
_ _
,
_._~
.. _ ...n,_ _
~
...
~M-
_ '_ _'"(';"
. _
10,:··.. ···.. ,·. . ;,..-..·.:···,
"
\'
.8
:,'
14 ...
z
o
22
~
':>
z
w
18
.....
....
et
i
-
'.'
./
I
I
..':
;i
.
I
"
., .. ,
( " ' !
,
,.;.1
",
"
:
I
,
/
I
,/1
.
I,'
1;'.1
-r.
"
.',
'
,f
~
,
,
,
.
v-.
I·'
•
".1"
,,'
" J '
' :
.,11 .
,,'
./
' ..
.
"
"I
!l
7.0. 8.0,
..
~,
'.'
,;
,
'6.0
.,'
.
./
' , ' "
.
\"
,
~I
:f,'
-j" i,'
II~"
'I,
"I .. ".:,
,".
o ,
,
I
\
. 1.0
2.0
3.0
4.0
\
.
'CURRENT (mA) .
.il/kure 4. Typical Sensitivity .
(Plotted
with frequency constant)
I
\
' . '
.
.
.
~
in the plots of typical 35·dB and BO-dB attenuation
chsracteristicsin Figure 4. "
i
\ '
'
.
The attenuation with a constant forward-bias var-
ieswith frequency. 'This variation is small at low
\.
,
. ' ,
.
.
levels of attenuation and more noticeable 'at higher
.values of attenuation (see Figure
5).
In addition.Jt
'should be noted that attenuation is.' a minimum at
. each end bf the'frequency band. Thus, the fre-
.quency band canbe exceeded provided a
dp~)a.da·
tion in attenuation range as well as other stecif'ica-
tions is acceptable.
,
\
i'
,
. Impedance Ma·tch .
The
PIN
Modulator has a good impedance match
, at. all levels of attenuation over Its frequency range.
This match is illustrated in Figure 6 which shows
the
SWR
of
a typical PIN
Modulator measured
..under both zero bias' and
maximum
forward
bias
conditions. Hence, with this constant match, fre-
.'
quency
pulli~g.
effects
due'
to the
PIN'
Modulator
are negligible, If the PIN Modulator is used outside"
specified frequency range,
SWR
chara~t;e.ristics
will
be degraded in addition to other' 'ope~l~ting specifi-
cations. .However, spurious responses can result
when, exceeding specified frequency r$l1g e.
\
.
I
I
"
.
\
"
I
,' 1
Temperature Stability
, I
...
.
. : .
I
,
'Ihe attenuation variationiwith
applied
bias
current
. .
and bias voltage at different
temperatures
is' illus-
. • '
tt!ate~, dOBver,~ l,ima1it0d't~anl;:
'e,
lin.
F~tg1·,I~e
,7
~ ,Atttenh'~la
\ Ion m .' .
vanes
mos •.
In .
ar
y
~1 ~/.
curren ,W. 1e
variation
'\VitI, voltage follo
s an
alri;kost perfect ex-
'",
"
.1._ ..' \ '
,"
"
..
,
.
"
'
'.'
I
' .
v,
I
,
',,\
.,
'.{
"
",
/ .
I
··/·41··
. ' : ' \ ·:·,' , . .
.......
' . "
.
\',
.
"
..
"
".',
'
.'
I;
,
\
;~\ .
,
~
;
.'
"
,
"
:,
I .
,
,
.
/
/
!
I
i"
I i
.............
.,
«,"
,
\
..
. . . , . . I
.'\
~DC':l~.;.;.....;,,
...............
:o...-.......
~..-..:...-.....:.....~ _"
_"'-.L..\-"-'_ _._......
,~".~~
Advertisement
