Introduction
Cobham MAL Ltd. line of VCO products provides excellent tuning linearity and phase noise for high performance solutions in hi-rel and military system applications.
These designs utilise silicon bipolar devices as the negative resistance generator. The frequency of operations is determined by a varactor diode that serves as a voltage variable capacitor. Silicon hyperabrupt varactors offer the lower phase noise performance. Careful selection of the varactor diodes manufactured in-house provides linear monotonic tuning characteristics requiring only simple external driver circuits.
Surface Mount and TO-8 Designs
This range of VCO’s is constructed using discrete chip device integrated onto a conventional alumina substrate. This is packaged into standard outline TO-8 and TO-8 SMT packages. These packages are hermetically sealed using resistance weld techniques. This compact rugged construction allows for simple installation on either through hole or surface mount PCB, and finds a wide range of applications in demanding military, hi-rel and commercial systems.
Connectorised VCO Designs
Cobham MAL Ltd. range of highly linear connectorised voltage controlled oscillators provides excellent phase noise performance in a rugged hermetic package. This range of VCO’s is constructed using discrete chip device integrated onto a conventional alumina substrate packaged into a machined housing. These packages are then hermetically seal sealed using laser-welding processes. The result is a compact rugged design suitable for most severe environmental conditions found in military and hi-rel applications. The coaxial connectors are removable allowing the designs to be integrated directly into microstrip or stripline circuits,
Applications
VCOs have a wide variety of applications where very fast tuning speeds are required. This feature along with superior output power flatness performance is critical for requirements in radar receivers or rapid generation of jamming signals in ECM transmitters. When high frequency stability is required for radar, communications, synthesisers of frequency converters, these VCOs may be integrated into phase lock loop circuitry. Low phase noise performance of the VCO, without highly linear tuning, simplifies loop filter design, enables the designer to achieve superior synthesiser performance. These VCOs can be qualified for high reliability and military requirements.
A wide range of custom designs are also available with output frequencies to 18 GHz.
Please contact the factory to discuss your requirements.
Cobham MAL VCO Capability – Connectorised Packages
Specification (guaranteed to -45°C to +85°C unless stated. Load impedance 50 ohm)
Frequency Range MHz | Linearity % Max | Pulling MHz Max | Frequency Drift MHz Max | Phase Noise @ 25°C | Harmonics dBc Max | O/P Power dBm Min | Power Supplies | Package Style |
100 KHz dBc/Hz Max | 1 MHz dBc/Hz Max | +15V mA Max | -15V mA Max |
4000-4500 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
4250-4750 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
4500-4750 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
4750-5250 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
5000-5500 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
5250-5750 | ±5 | 2 | 30 | -106 | -126 | -12 | +13 | 75 | 75 | VCO A |
5500-6000 | ±5 | 5 | 30 | -100 | -120 | -12 | +13 | 75 | 75 | VCO A |
5750-6250 | ±5 | 5 | 50 | -100 | -120 | -12 | +13 | 75 | 75 | VCO A |
5750-6250 | ±5 | 5 | 50 | -100 | -120 | -12 | +20 | 225 | 75 | VCO B |
6000-6500 | ±5 | 5 | 50 | -100 | -120 | -12 | +13 | 75 | 75 | VCO A |
6000-6500 | ±5 | 5 | 50 | -100 | -120 | -12 | +20 | 225 | 75 | VCO B |
6250-6750 | ±5 | 5 | 50 | -100 | -120 | -12 | +13 | 75 | 75 | VCO A |
6250-6750 | ±5 | 5 | 50 | -100 | -120 | -12 | +20 | 225 | 75 | VCO B |
6500-7000 | ±5 | 5 | 50 | -100 | -120 | -12 | +10 | 75 | 75 | VCO A |
6500-7000 | ±5 | 5 | 50 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
6750-7250 | ±5 | 5 | 50 | -98 | -118 | -12 | +10 | 75 | 75 | VCO A |
6750-7250 | ±5 | 5 | 50 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
7000-7500 | ±5 | 5 | 50 | -98 | -118 | -12 | +10 | 75 | 75 | VCO A |
7000-7500 | ±5 | 5 | 70 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
7250-7750 | ±5 | 5 | 70 | -98 | -118 | -12 | +10 | 75 | 75 | VCO A |
7250-7750 | ±5 | 5 | 70 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
7500-8000 | ±5 | 5 | 70 | -98 | -118 | -12 | +10 | 75 | 75 | VCO A |
7500-8000 | ±5 | 5 | 70 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
7750-8250 | ±5 | 5 | 70 | -98 | -118 | -12 | +10 | 75 | 75 | VCO A |
7750-8250 | ±5 | 5 | 70 | -98 | -118 | -12 | +20 | 225 | 75 | VCO B |
8000-9000 | ±10 | 5 | 80 | -95 | -115 | -12 | +10 | 75 | 75 | VCO A |
8000-9000 | ±10 | 5 | 80 | -95 | -115 | -12 | +20 | 225 | 75 | VCO B |
8500-9500 | ±10 | 5 | 80 | -95 | -115 | -12 | +10 | 75 | 75 | VCO A |
8500-9500 | ±10 | 5 | 80 | -95 | -115 | -12 | +20 | 225 | 75 | VCO B |
9000-10000 | ±10 | 5 | 80 | -95 | -115 | -12 | +10 | 75 | 75 | VCO A |
9000-10000 | ±10 | 5 | 80 | -95 | -115 | -12 | +20 | 225 | 75 | VCO B |
Notes:
1. Frequency Pushing 100 KHz/V for voltages -13 to -18V (max)
2. Spurious Output -60 dBc max
3. Tuning Voltage 0 to +16V
4. Settling Time 1µS from 50% VT to ±3 MHz of final frequency (typical) 5. Output Power Variation ±2.5 dB max (all causes)
6. Operating Temperature Range -55°C to +85°C
7. Storage Temperature Range -55°C to +100°C
8. Pulling is specified into 1.5:1 VSWR and phase
9. Case size (excluding connectors) VCO A 46 x 27 x 10 mm VCO B 46 x 35 x 10 mm
Parameter | Absolute Maximum |
Tuning Voltage | 0 to 20V |
Supply Voltage | +18V |
Storage Temperature | +125°C |
Cobham MAL VCO Capability – Connectorised Packages
Specification (guaranteed to -45°C to +85°C unless stated. Load impedance 50 ohm)
Frequency Range MHz | Pulling MHz/V Max | Pulling MHz Max | Frequency Drift MHz Max | Phase Noise @ 25°C | Harmonics dBc Max | O/P Power dBmMin | O/P PowerVariationdBm Max | DCCurrent@+12V mAMax |
100 KHz dBc/Hz Max | 1 MHz dBc/Hz Max |
400-600 | 5 | 30 | 15 | -110 | -130 | -10 | 10 | ±2 | 50 |
500-700 | 5 | 30 | 15 | -110 | -130 | -10 | 10 | ±2 | 50 |
600-800 | 10 | 35 | 25 | -108 | -128 | -10 | 10 | ±2 | 50 |
700-900 | 10 | 35 | 25 | -108 | -128 | -10 | 10 | ±2 | 50 |
800-1000 | 10 | 35 | 25 | -108 | -128 | -10 | 10 | ±2 | 50 |
750-1250 | 12 | 40 | 40 | -105 | -125 | -10 | 10 | ±2.5 | 50 |
1000-1500 | 12 | 40 | 40 | -105 | -125 | -10 | 10 | ±2.5 | 50 |
1250-1750 | 12 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
1500-2000 | 12 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
1750-2250 | 12 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
2000-2500 | 15 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
2250-2750 | 15 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
2500-3000 | 15 | 40 | 60 | -102 | -122 | -10 | 10 | ±2.5 | 50 |
2750-3250 | 15 | 40 | 60 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
3000-3500 | 15 | 40 | 80 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
3250-3750 | 15 | 40 | 80 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
3500-4000 | 15 | 40 | 80 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
3750-4250 | 15 | 40 | 100 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
4000-4500 | 15 | 40 | 100 | -100 | -120 | -10 | 10 | ±2.5 | 50 |
4250-4750 | 15 | 40 | 100 | -98 | -118 | -12 | 10 | ±2.5 | 50 |
4500-5000 | 15 | 40 | 100 | -98 | -118 | -12 | 10 | ±2.5 | 50 |
4750-5250 | 15 | 40 | 100 | -98 | -118 | -12 | 10 | ±2.5 | 50 |
5000-5500 | 15 | 50 | 100 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
5250-5750 | 15 | 50 | 100 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
5500-6000 | 15 | 50 | 120 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
5750-6250 | 15 | 50 | 120 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
6000-6500 | 15 | 50 | 120 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
6250-6750 | 15 | 60 | 120 | -95 | -115 | -12 | 10 | ±2.5 | 100 |
6500-7000 | 15 | 60 | 120 | -93 | -113 | -12 | 10 | ±2.5 | 100 |
6750-7250 | 15 | 60 | 120 | -93 | -113 | -12 | 10 | ±2.5 | 100 |
7000-7500 | 15 | 60 | 120 | -93 | -113 | -12 | 10 | ±2.5 | 100 |
7250-7750 | 15 | 60 | 120 | -93 | -113 | -12 | 10 | ±2.5 | 100 |
7500-8000 | 15 | 60 | 120 | -93 | -113 | -12 | 10 | ±2.5 | 100 |
2000-3000 | 15 | 60 | 80 | -98 | -118 | -10 | 10 | ±2.5 | 100 |
2500-3500 | 15 | 60 | 100 | -98 | -118 | -10 | 10 | ±2.5 | 100 |
3000-4000 | 15 | 60 | 100 | -98 | -118 | -10 | 10 | ±2.5 | 100 |
3500-4500 | 15 | 60 | 100 | -98 | -118 | -10 | 10 | ±2.5 | 100 |
4000-5000 | 15 | 60 | 100 | -95 | -115 | -10 | 10 | ±2.5 | 100 |
4000-5500 | 15 | 60 | 100 | -95 | -115 | -10 | 10 | ±2.5 | 100 |
2000-4000 | 15 | 60 | 120 | -95 | -115 | -10 | 10 | ±2.5 | 100 |
3000-5000 | 15 | 60 | 120 | -95 | -115 | -10 | 10 | ±2.5 | 100 |
Notes:
1. Frequency Pushing is specified for voltages +12V ±5%
2. Frequency Pulling is specified into 1.5:1 VSWR any phase.
3. Spurious Output -60 dBc max.
4. Tuning Voltage 0 to +16V
5. Settling Time 1µS from 50% VT to ±3 MHz of final frequency (typical) 6. Operating Temperature Range -55°C to +85°C
7. Storage Temperature Range -55°C to +100°C
8. Operating Voltage +12V nominal
9. 3dB Modulation Bandwidth 10 Mhz min (50 ohm source)
Parameter | Absolute Maximum |
Tuning Voltage | 0 to 20V |
Supply Voltage | +14V |
Storage Temperature | +125°C |