18–40 GHz GaAs MMIC Voltage Variable Attenuator AV850M2-00 Features Chip Outline 0.982 ■ Dual Voltage Control ■ 35 dB Attenuation Range ■ Triple Gate 0.25 µm MESFET Design 1.050 0.911 ■ +10 dBm P1 dB All Attenuation States ■ 100% On-Wafer RF and DC Testing ■ 100% Visual Inspection to MIL-STD-883 MT 2010 0.314 0.097 Description 1.500 0.750 Alpha’s AV850M2-00 MMIC voltage variable attenuator is a standard TEE configuration incorporating triple-gate 0.25 µm power MESFETs. The attenuator has a typical insertion loss of 3 dB over the 18–40 GHz band. The attenuation range is 35 dB while typical I/P and O/P return loss is better than 6 dB. The chip uses Alpha’s proven 0.25 µm MESFET technology and is based upon MBE layers and electron beam lithography for the highest uniformity and repeatability. The MMICs employ surface passivation to ensure a rugged, reliable part with through-substrate via holes and gold-based backside metallization to facilitate a conductive epoxy die attach process. This chip incorporates triple-gate FETs which results in less attenuation variation over temperature as well as better power handling performance at all attenuation states. All chips are screened for insertion loss, full attenuation and I/P and O/P match over the 18–40 GHz band for guaranteed performance. 0.000 0.000 Dimensions indicated in mm. All DC (V) pads are 0.1 x 0.1 mm and RF In, Out pads are 0.07 mm wide. Chip thickness = 0.1 mm. Absolute Maximum Ratings Characteristic Value Operating Temperature (TC) -55°C to +90°C Storage Temperature (TST) -65°C to +150°C Control Voltage (VC) -7 VDC Power In (PIN) 30 dBm Junction Temperature (TJ) 175°C Electrical Specifications at 25°C Condition Symbol Min. Typ.2 Maximum Attenuation VC = -1 V, VC2 = -0.25 V F = 18–35 GHz ISO 20 30 Minimum Attenuation VC = -1 V, VC2 = -3.25 V F = 18–35 GHz IL 2 3 dB F = 18–35 GHz RL -10 -6 dB VC = 0 V, VC2 = -0.8 V F = 35–40 GHz ISO Parameter Input/Output Return Loss Maximum Attenuation Minimum Attenuation Input/Output Return Loss Input Power at 1 dB Compression (For All Attenuation Levels)1 Thermal Resistance 1. Not measured on a 100% basis. 20 Max. Unit dB 35 dB VC = 0 V, VC2 = -3.25 V F = 35–40 GHz IL 3 4 dB F = 35–40 GHz RL -10 -5 dB P1 dB 10 dBm ΘJC 101 °C/W 2. Typical represents the median parameter value across the specified frequency range for the median chip. Alpha Industries, Inc. [781] 935-5150 • Fax [617] 824-4579 • Email [email protected] • www.alphaind.com Specifications subject to change without notice. 9/00A 1 18–40 GHz GaAs MMIC Voltage Variable Attenuator AV850M2-00 Typical Performance Data VC2: -1.6 – -3.0 Attenuation (dB) -5 -10 -15 -1.4 0 -1.2 -5 -20 -1.0 -0.8 -25 -30 -0.6 -0.4 -0.2 0.0 -35 -40 Knee Knee Knee Voltage 1 Voltage 2 Voltage 3 -15 -20 -30 -35 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 Frequency (GHz) Example Chip 1 Example Chip 2 Example Chip 3 -40 -3.25 Attenuation vs. Frequency (VC1 = 0 V) Input Power at 1 dB * -25 -45 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 -2 -20 -18 -16 -14 -12 -10 -8 VC1 = -1V * -10 Attenuation (dB) 0 -0.25 Control Voltage VC2 (V) Example Chip-to-Chip Variation for Any Single-Frequency of Operation (Low-Frequency Band) * 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 Attenuation (dB) Attenuation vs. 1.0 dB Compression RF RF 0 Attenuation (dB) -5 20 GHz -10 30 GHz -15 -20 -25 -30 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 -35 -40 VC1 = 0 V -45 -3.0 -2.6 -2.2 -1.8 -1.4 -1.0 -0.6 -0.2 0 Circuit Schematic RF IN RF OUT Control Voltage VC2 (V) Attenuation vs. Control Voltage VC2 VC1 2 Alpha Industries, Inc. [781] 935-5150 • Fax [617] 824-4579 • Email [email protected] • www.alphaind.com Specifications subject to change without notice. 9/00A