18–40 GHz GaAs MMIC Voltage Variable Attenuator
AV850M2-00
Typical Performance Data
VC2
-1.6 – -3.0
:
Knee
Knee
Knee
0
-5
Voltage 1 Voltage 2 Voltage 3
-1.4
0
-5
-10
-15
-20
-25
-30
-35
-40
-45
VC1 = -1V
*
-1.2
-10
-15
-20
-25
-30
-35
-40
-1.0
-0.8
*
-0.6
-0.4
-0.2
0.0
Example Chip 1
Example Chip 2
Example Chip 3
20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
Frequency (GHz)
-3.25
-0.25
Attenuation vs. Frequency (V = 0 V)
C1
Control Voltage VC2 (V)
Example Chip-to-Chip Variation for Any
Single-Frequency of Operation
(Low-Frequency Band)
28
26
24
22
20
18
16
14
12
10
8
* Asterisk in graph indicates guaranteed attenuation limits from the Electrical
Specification table (knee voltage can vary from -3.25 V to approximately -1.0 V).
Bias Arrangement
VC2
6
4
2
0
-2
-20 -18 -16 -14 -12 -10 -8 -6 -4 -2
0
Attenuation (dB)
Attenuation vs. 1.0 dB Compression
RF
RF
0
-5
20 GHz
30 GHz
-10
-15
-20
-25
-30
-35
-40
-45
VC1
40 GHz
VC1 controls the series devices, adjust for optimum VSWR.
VC2 controls the shunt devices, adjust to set attenuation.
Recommended Control Voltages:
For frequency 18–35 GHz: VC1 = -1 V, VC2 = -0.25 to -3.25 V.
For frequency 35–40 GHz: VC1 = 0 V, VC2 = -0.8 to -3.25 V.
50 GHz
VC1 = 0 V
Circuit Schematic
RF IN
-3.0 -2.6 -2.2 -1.8 -1.4 -1.0 -0.6 -0.2
0
RF OUT
Control Voltage VC2 (V)
Attenuation vs. Control Voltage
VC2
VC1
2
Alpha Industries, Inc. [781] 935-5150 • Fax [617] 824-4579 • Email sales@alphaind.com • www.alphaind.com
Specifications subject to change without notice. 9/00A
ALPHA [ ALPHA INDUSTRIES ]
