Series 195 Octave-Band PIN Diode Attenuator/Modulator
Applicaton Notes for
Microwave Attenuators
SERIES 195
Series 195 current-controlled attenuator/modulators provide small size with greater
than octave-bandwidth performance at low cost. All models except the 1950A*
provide a minimum of 60 dB of attenuation with fall times of 20 nsec max, and rise
times ranging from 25 nsec for the 1951 and 1952 to 125 nsec max for the 1956
and 1958. The 1950A* provides a minimum of 80 dB of attenuation with a fall time
of 50 nsec max and a rise time of 250 nsec max. These characteristics make this
series suitable for a wide range of applications including level setting, complex
amplitude modulation, pulse modulation and high-speed switching. The eight
models in the Series 195 encompass a frequency range from 0.5 to 18 GHz. All
models except the 1950A* are capable of extended bandwidth operation, typically
3:1, with only moderate degradation in performance at the band edges.
As shown in figures 1 and 2 below, the RF circuit employed in all models except
the Model 1950A* uses two shunt arrays of PIN diodes and two quadrature hybrid
couplers. The quadrature hybrids are of a unique GMC microstrip design which are
integrated with the diode arrays to yield a minimal package size. The RF circuit
employed in the Model 1950A* uses one shunt array of PIN diodes with input and
output impedance matching circuits.
*Model 1950A is a special-order product. Consult factory before ordering.
l
l
l
l
l
Absorptive
Current controlled
0.5 to 18 GHz frequency range
High performance MIC quadrature
hybrid design
High speed
FLATNESS (± dB)
AT MEAN ATTENUATION LEVELS UP TO
MODEL FREQUENCY RANGE (GHz) MAX. INSERTION LOSS MAX. VSWR 10 dB
1950A*
1951
1952
1953
1954
1955
1956
1958
0.5 - 1.0
1.0 - 2.0
0.75 - 2.25
(1)
2.0 - 4.0
1.5 - 4.5
(1)
2.6 - 5.2
1.95 - 5.85
(1)
4.0 - 8.0
3.0 - 9.0
(1)
5.0 - 10.0
3.75 - 11.25
(1)
6.0 - 12.0
4.5 - 13.5
(1)
8.0 - 18.0
6.0 - 18.0
(1)
1.4
1.3
1.4
1.5
1.6
1.7
1.8
2.0
2.1
2.2
2.3
2.3
2.4
2.5
(2)
2.5
(2)
2.0
1.5
2.0
1.5
2.0
1.6
2.1
1.7
2.2
1.7
2.2
1.8
2.2
1.8
(2)
1.8
(2)
0.3
0.3
0.5
0.3
0.5
0.3
0.5
0.3
0.5
0.5
0.7
0.7
0.9
0.7
0.9
20 dB
0.8
0.8
1.4
0.8
1.4
0.8
1.4
0.8
1.4
0.9
1.4
1.0
1.5
1.0
1.5
40 dB
1.7
1.5
3.0
1.5
3.0
1.5
3.0
1.5
3.0
1.5
3.0
1.5
3.0
1.5
3.0
60 dB
2.2
1.6
3.5
1.6
3.5
1.6
3.5
1.6
3.5
1.6
3.5
1.6
3.5
1.6
3.5
80 dB
3.2
(1) Specifications for the extended frequency ranges are typical.
(2) Except from 16-18 GHz w here insertion loss is 3.5 dB max and VSWR is 2.0 max
*Model 1950A is a special-order product. Consult factory before ordering.
PERFORMANCE CHARACTERISTICS
Mean Attenuation Range
1950A* ....................................... 80 dB
All other units ............................ 60 dB
Monotonicity
............................... Guaranteed
Phase Shift
..................................
See Application Note
Temperature Effects
................ See Fig. 3
Power Handling Capability
Without Performance Degradation
1950A*,1951 .......................... 10 mW cw or peak
All other units ......................... 100 mW cw or peak
Survival Power (from -65°C to +25°C;
see Fig. 4 for higher temperatures)
All units .................................... 1 W average 25W peak (1
µsec max pulse width)
*Model 1950A is a special-order product. Consult factory before ordering.
Switching Speed
Fall Time
195OA* .....................................
All other units ...........................
Rise Time
195OA* .....................................
All other units ...........................
195OA* .....................................
All other units .........................
250 nsec max
(3)
125 nsec max
(3)
5 to 35 mA
15 to 70 mA
50 nsec max
(3)
20 nsec max
(3)
Bias Current for Maximum Attenuation
(3) For attenuation steps of 10 dB or more.
Fig 3—Series 195, typical effects of temperature on attenuation
ENVIRONMENTAL RATINGS
Operating Temperature
Range.....................................
-54°C to + 125°C
Non-Operating
Temperature Range
.......... -65°C to + 125°C
Humidity
................................... MIL-STD-202F, Method 103B,
Cond. B (96 hrs. at 95%)
Shock
....................................... MIL-STD-202F, Method 213B,
Cond. B (75G, 6 msec)
Vibration
.................................. MIL-STD-202F, Method 204D,
Cond. B (.06" double amplitude
or 15G, whichever is less)
Altitude
.................................... MIL-STD-202F, Method 105C,
Cond. B (50,000 ft.)
Temp. Cycling
......................... MIL-STD-202F, Method 107D,
Cond. A, 5 cycles
AVAILABLE OPTIONS
Option No.
3
7
10
64
64A
Description
SMA female bias connector
Two SMA male rf connectors
One SMA male (J1) and one SMA
female (J2) rf connector
SMC male bias connector
SMB male bias connector
DIMENSIONS AND WEIGHTS
Dimensional Tolerances, unless otherw ise indicated: .XX±.02; .XXX±.005
Herley - General Microwave specializes in developing and producing customized
microwave components
and
millimeter wave products
for the defense and aerospace
industries as well as for non-defense applications such as communication systems. Herley General Microwave produces the industry standard General Microwave line of
off-the-shelf catalog RF components. If you are looking for a
solid state power amplifier, microwave synthesizer
or other
microwave oscillators,
microwave receiver,
microwave switch, microwave attenuator,
microwave limiter,
microwave phase shifter,
or
microwave IQ vector modulator;
we can produce components meeting your
requirements at a very competitive price. We also produce high quality customized
integrated microwave assemblies
such as up and down converters, DLVAs, beam
forming networks, front ends, or switched bank filters, that can be used in a wide variety of demanding applications.
Herley General Microwave (HGMI),
a subsidiary of
Herley Industries
provides solutions for electronic warfare systems, phased array radar systems, electronic warfare simulators, test equipment and test systems and other
defense and non-defense systems. We look forward to working with you, so please
contact us
today.
京公网安备 11010802033920号
EEWORLD
