Voltage Controlled Variable Attenuators up to 170 GHz

Features  
  • Low insertion losses
  • High isolation
  • Low cost 
  • Low switching time
  • Full band operation
  • Easy to use
Applications Voltage Controlled Variable Attenuators up to 170 GHz
  • Alternative for polarisation attenuators
  • Alternative for p-i-n modulators
  • AM of microwave signals
  • Power control
  • Lock-in detection systems
Description  
     ELVA-1 series Voltage-Controlled Variable Attenuators VCVA are built on the base of PIN diodes as an active element. Modern technology allows to combine advantages of different types of attenuators and modulators in one device. Full band operation, accuracy, 60 dB attenuation range and small insertion losses are comparable with specification for polarization attenuators. On the other hand a small switching time allows to use the device instead of Faraday rotation ferrite modulators or ON/OFF type p-i-n modulators. The attenuators are designed as a gold covered waveguide section and have a high reliability. The basic unit is a current controlled attenuator. We propose also an external driver which provides a voltage current conversion and a switching time up to the 25 μs. We supply each device with personal calibration characteristics. Typical characteristics for the VCVA-10 model are shown on two plots below: attenuation versus control voltage with fixed frequency and attenuation versus frequency with different control voltages.  

ELVA-1 VCVA Attenuation vs Bias diagram

ELVA-1 VCVA's Attenuation vs Frequency and Bias current diagram

ELVA-1 VCVA's "WSWR vs Frequency and Bias current" diagram

Specifications

Model VCVA-42 VCVA-28 VCVA-22 VCVA-19 VCVA-15 VCVA-12 VCVA-10 VCVA-08 VCVA-06
Frequency Band K Ka Q U V E W F D
Range, GHz 18-26.5 26-40 33-50 40-60 50-75 60-90 75-110 90-140 110-170
VSWR (typ.) Ibias 0 mA 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5
VSWR (typ.) Ibias 30 mA 2 2 2 2 2 2 2 2 2
Wideband Version
Bandwidth, % 20 15 15 15 15 15 15 15 15
Insertion Loss, dB (typ) 0.7 0.7 0.8 0.8 0.8 1 1 1 1
Isolation, dB (min) 50* 50* 50* 50* 50* 50* 50* 50* 50*
Peak Power, W(max) 1 1 1 1 1 1 1 1 1
Switching Time, μs ** 100 50 50 50 50 50 25 25 25
DC Bias Input, mA 100 100 100 100 100 100 100 100 100
Full band Version
Bandwidth, % 100 100 100 100 100 100 100 100 100
Insertion Loss 1.0 1.8 2 2 2 2 2 3 3
Isolation, dB (min) 50* 50* 50* 50* 50* 50* 50* 50* 45*
Peak Power, W(max) 1 1 1 1 1 1 1 1 1
Switching Time, μs ** 100 50 50 50 50 50 25 25 25
DC Bias Input, mA 100 100 100 100 100 100 100 100 100

*The models with 60 dB Isolation are available upon request

**Guaranteed for Rise Time 0-90% RF and Fall Time 100-10% RF. Models with twice lower switching time are available upon request for the 50-170 GHz frequency range.

 Mechanical specifications

ELVA-1 provides different options:

 – Flat mount flanges

ELVA-1 Solid State Attenuators, Flat mount flanges

– With extension waveguides

ELVA-1 Solid State Attenuators with extension waveguides