Herley: Series D195 Octave-Band
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Series D195 Octave-Band
PIN Diode Attenuator/Modulators
How to Buy
Application Notes
The Series D195 voltage-controlled linearized attenuator/modulators are integrated
assemblies consisting of a Series 195 unit and a hybridized driver circuit which
provides a nominal transfer function of 10 dB per volt. (See figure 1 below.)
Absorptive
Linearized
Frequency range: 0.5 to 18 GHz
High performance MIC quadrature
hybrid design
High speed
All of the Series D195 units except the D195OA* exhibit fall times of 20 nsec max
and rise times of 1.5 µsec max for attenuation steps of 10 dB or more. For smaller
excursions, the fall times can increase to several hundred nsec, while the rise
times remain essentially unchanged. In applications where a rapid return to
insertion loss from any level of attenuation is required, Option 59 is available. With
this option, an external pulse is applied to trigger a high-speed reset circuit, and
recovery times of 200 nsec max are obtained. Where use of an external reset
pulse as described above is not feasible, an internal reset option (Option 58) is
available which will automatically reset the unit to insertion loss within 200 nsec for
a step of 50 dB or more. The fall and rise time specifications for the D1950A* are
500 nsec max and 10 µsec max, respectively. Options 58 and 59 are not available
for this model.
*Model D1950A is a special-order product. Consult factory before ordering.
ALL UNITS
IN THIS SERIES
ARE EQUIPPED
WITH INTEGRATED DRIVERS
FLATNESS (±dB)
MODEL FREQUENCY RANGE (GHz)
MAX. INSERTION LOSS (dB)
MAX. VSWR AT MEAN ATTENUATION LEVELS UP TO
10 dB 20 dB 40 dB 60 dB 80 dB
D1950A*
D1951
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
1.6
1.7
1.8
1.9
2.0
2.1
2.4
2.5
2.6
2.7
2.7
2.8
3.0
(2)
3.0
(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
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
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
3.0
1.6
3.5
1.6
3.5
1.8
3.5
1.6
3.5
1.6
3.5
1.6
3.5
1.6
3.5
3.6
D1952
D1953
D1954
D1955
D1956
D1958
*Model 1950A is a special-order product. Consult factory before ordering.
(1) Specifications for the extended frequency ranges are typical.
(2) Except from 16 - 18 GHz where insertion loss is 4.0 dB max and VSWR is 2.0 max.
PERFORMANCE CHARACTERISTICS
Mean Attenuation Range
D1950A*
..........................
80 dB
All other units
...................
60dB
Accuracy of Attenuation
Switching Characteristics
Off Time
D195OA*
...................
600 nsec max
All other units
.............
100 nsec max
On Time
D1950A*
...................
Fall Time
D1950A*
...................
Rise Time
D195OA*
...................
10 µsec max
All other units
.............
1.5 µsec max
Nominal Control Voltage Characteristics Range
Operating Maximum
D195OA*
0 to + 8V
± 15V
All Other Units
0 to + 6V
± 15V
Transfer
Function
.................
Input
Impedance
...................
Modulation Bandwidth
Small Signal
D195OA*
...................
25 kHz
All other units
.............
500 kHz
10 dB / volt
10 Kohms
500 nsec max
All other units
.............
20 nsec max
10 µsec max
All other units
.............
1.6 µsec max
±
0.5 dB
> 30 to 50 dB
................... ±
1.0 dB
> 50 to 60 dB
................... ±
1.5 dB
> 60 to 80 dB
................... ±
2.0 dB
(D195OA*only)
Monotonicity
......................
Guaranteed
Phase Shift
........................
See Application Note
Temperature Coefficient
...... ±
0.025 dB/ C
Power Handling Capability
Without Performance Degradation
D1950A*,D1951
............
10 mW cw or peak
All other units
................
100 mW cw or peak
Survival Power (from -65%C to +25%C;
see Fig. 2 for higher temperatures)
All units
..........................
1 W average 25W peak (1
µ
sec max
pulse width)
O to 3OdB
.......................
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11/17/2009
Herley: Series D195 Octave-Band
Page 2 of 2
Large Signal
D195OA*
...................
5 kHz
50 kHz
All other
units .................
+12V 5%, 100 mA
Power Supply
Requirements
..............
-12V 5%, 50 mA
Less than 0.1 dB / volt change in
Power Supply
Rejection
.....................
either supply
*Model 1950A is a special-order product. Consult factory before ordering.
ENVIRONMENTAL RATINGS
Operating Temperature
Range
...................................
-54%C to + 110%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
58
Description
SMA female control connector
Two SMA male rf connectors
One SMA male (J1) and one
SMA female (J2) RF connector
Internally-generated reset to
insertion loss (not available on
D1950A)
(1)
Externally-triggered reset to
insertion loss (not available on
D1950A*)
(2)(3)
20 dB / volt transfer function with
0 to +3V control signal input (+4V
for the D1950A*)
± 15 volt operation
SMC male control connector
SMB male control connector
59
61
62
64
64A
(1) Where use of an Option 59 external reset pulse (see note 2 below) is not feasible, this option is available which will
automatically sense the slope and magnitude of the control signal and reset the unit to the insertion loss state within
200 nsec for a stop of 50 dB or more.
(2) An external terminal is provided for the user to apply a fast (10 nsec, max rise time) positive-going 3-volt pulse at
least 0.5 µsec wide to accelerate the return of the attenuator to the insertion loss state with the simultaneous
lowering of the control signal to the zero voltage level. This reset can be accomplished within 200 nsec.
(3) The input impedance of units equipped with Option 59 is a circuit equivalent to approximately 50 pF in series with a
parallel combination of 100 pF and 1000 ohms.
Dimensions and Weights
* Model 1950A is a special-order product. Consult factory before ordering.
Dimensional Tolerances, unless otherwise indicated: .XX ±.02; .XXX ±.005
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11/17/2009
