HMC346 v02.0907 ATTENUATORS - CHIP 2 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Typical Applications Features This attenuator is ideal for use as a VVA for DC - 20 GHz applications: Wide Bandwidth: DC - 20 GHz • Point-to-Point Radio 32 dB Attenuation Range • VSAT Radio Die Size: 0.85 x 0.85 x 0.1 mm Functional Diagram General Description Low Phase Shift vs. Attenuation The HMC346 die is an absorptive Voltage Variable Attenuator (VVA) operating from DC - 20 GHz. It features an on-chip reference attenuator for use with an external op-amp to provide simple single voltage attenuation control, 0 to -3V. The device is ideal in designs where an analog DC control signal must control RF signal levels over a 30 dB amplitude range. For plastic packaged version, see the HMC346MS8G which operates from DC - 8 GHz. Electrical Specifi cations, TA = +25° C, 50 ohm system Parameter Typ. Max. Units 1.7 2.2 2.3 2.8 dB dB Insertion Loss Attenuation Range DC - 12 GHz: DC - 20 GHz: 27 22 32 25 dB dB Return Loss DC - 12 GHz: 12 - 20 GHz: 6 10 10 15 dB dB 2 8 ns ns Switching Characteristics 2-2 Min. DC - 12GHz: DC - 20 GHz: tRISE, tFALL (10/90% RF): tON, tOFF (50% CTL to 10/90% RF): Input Power for 0.25 dB Compression (0.5 - 20 GHz) Min. Atten: Atten. >2 dB: +8 +4 dBm dBm Input Third Order Intercept (0.5 - 20 GHz) (Two-tone Input Power = -8 dBm Each Tone) Min. Atten: Atten. >2 dB: +25 +10 dBm dBm For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com HMC346 v02.0907 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Relative Attenuation 0 0 -0.5 -5 -1 -10 -1.5 -2 -2.5 +25 C -55 C +85 C -3 -3.5 2 -15 -20 -25 -30 -35 -4 -40 0 5 10 15 20 25 0 5 FREQUENCY (GHz) 0 20 25 0 CONTROL VOLTAGE (Vdc) MIN 5 dB MAX -5 RETURN LOSS (dB) 15 Relative Attenuation vs. Control Voltage @ 10 GHz Return Loss vs. Attenuation -10 -15 -20 -25 -30 -35 V1 +25 C V1 -55 C V1 +85 C V2 +25 C V2 -55 C V2 +85 C -0.5 -1 -1.5 -2 -2.5 -3 0 5 10 15 20 25 0 5 10 15 20 25 30 RELATIVE ATTENUATION (dB) FREQUENCY (GHz) Relative Attenuation vs. Control Voltage @ 20 GHz Relative Phase 240 0 220 180 160 140 CONTROL VOLTAGE (Vdc) 5 dB 10 dB 15 dB 20 dB 25 dB 30 dB max 200 RELATIVE PHASE (DEG) 10 FREQUENCY (GHz) ATTENUATORS - CHIP ATTENUATION (dB) INSERTION LOSS (dB) Insertion Loss vs. Temperature 120 100 80 60 40 V1 +25 C V1 -55 C V1 +85 C V2 +25 C V2 -55 C V2 +85 C -0.5 -1 -1.5 -2 -2.5 20 0 -3 0 5 10 15 FREQUENCY (GHz) 20 25 0 5 10 15 20 25 RELATIVE ATTENUATION (dB) For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com 2-3 HMC346 v02.0907 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Input IP3 vs. Attenuation* 25 60 20 50 IP2 (dBm) IP3 (dBm) 70 15 10 40 30 0 dB 3 dB 6 dB 10 dB 5 0 dB 3 dB 6 dB 10 dB 20 0 10 0 5 10 15 20 0 5 FREQUENCY (GHz) 20 10 15 P1dB (dBm) 0 dB (REF) 6 dB 0 -5 5 0 dB (REF) 6 dB -5 0 5 10 15 20 0 5 FREQUENCY (GHz) 10 15 20 FREQUENCY (GHz) Absolute Maximum Ratings Second Harmonic vs. Attenuation* 80 70 60 RF Input Power +18 dBm Control Voltage Range +1 to -5 Vdc Storage Temperature -65 to +150 °C Operating Temperature -55 to +85 °C 50 40 ELECTROSTATIC SENSITIVE DEVICE OBSERVE HANDLING PRECAUTIONS 0 dB 3 dB 6 dB 10 dB 30 20 0 5 10 15 20 FREQUENCY (GHz) *Two-tone input power = -8 dBm each tone, 1 MHz spacing. 2-4 20 10 0 -10 SECOND HARMONIC (dBc) 15 Input 1 dB Compression vs. Attenuation 15 5 10 FREQUENCY (GHz) Input 0.25 dB Compression vs. Attenuation 0.25 dB (dBm) ATTENUATORS - CHIP 2 Input IP2 vs. Attenuation* 30 For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com HMC346 v02.0907 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Outline Drawing ATTENUATORS - CHIP 2 1. ALL DIMENSIONS ARE IN INCHES (MILLIMETERS). 2. TYPICAL BOND PAD IS .004” SQUARE. 3. TYPICAL BOND PAD SPACING IS .006” CENTER TO CENTER EXCEPT AS NOTED. 4. BACKSIDE METALIZATION: GOLD 5. BACKSIDE METAL IS GROUND 6. BOND PAD METALIZATION: GOLD Die Packaging Information [1] Standard Alternate GP-2 [2] [1] Refer to the “Packaging Information” section for die packaging dimensions. [2] For alternate packaging information contact Hittite Microwave Corporation. Pad Descriptions Pad Number Function Description 1, 2 RF1 Input, RF2 Output This pad is DC coupled and matched to 50 Ohm. Blocking capacitors are required if RF line potential is not equal to 0V. 3, 6 V2, V1 Control Input (Master). 4 I Control Input (Slave). 5 500 This pad must be DC grounded. GND Die bottom must be connected to RF ground. Interface Schematic For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com 2-5 HMC346 v02.0907 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Single-Line Control Driver ATTENUATORS - CHIP 2 External op-amp control circuit maintains impedance match while attenuation is varied. Input control ranges from 0 Volts (min. attenuation) to -3.0 Volts (max. attenuation.) Assembly Diagram 2-6 For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com HMC346 v02.0907 GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, DC - 20 GHz Mounting & Bonding Techniques for Millimeterwave GaAs MMICs 50 Ohm Microstrip transmission lines on 0.127mm (5 mil) thick alumina thin film substrates are recommended for bringing RF to and from the chip (Figure 1). If 0.254mm (10 mil) thick alumina thin film substrates must be used, the die should be raised 0.150mm (6 mils) so that the surface of the die is coplanar with the surface of the substrate. One way to accomplish this is to attach the 0.102mm (4 mil) thick die to a 0.150mm (6 mil) thick molybdenum heat spreader (moly-tab) which is then attached to the ground plane (Figure 2). 0.102mm (0.004”) Thick GaAs MMIC Wire Bond 0.076mm (0.003”) RF Ground Plane Microstrip substrates should brought as close to the die as possible in order to minimize bond wire length. Typical die-to-substrate spacing is 0.076mm to 0.152 mm (3 to 6 mils). 0.127mm (0.005”) Thick Alumina Thin Film Substrate Figure 1. Handling Precautions Follow these precautions to avoid permanent damage. Storage: All bare die are placed in either Waffle or Gel based ESD protective containers, and then sealed in an ESD protective bag for shipment. Once the sealed ESD protective bag has been opened, all die should be stored in a dry nitrogen environment. Cleanliness: Handle the chips in a clean environment. DO NOT attempt to clean the chip using liquid cleaning systems. Static Sensitivity: strikes. 0.102mm (0.004”) Thick GaAs MMIC Wire Bond 0.076mm (0.003”) 2 ATTENUATORS - CHIP The die should be attached directly to the ground plane eutectically or with conductive epoxy (see HMC general Handling, Mounting, Bonding Note). RF Ground Plane Follow ESD precautions to protect against ESD Transients: Suppress instrument and bias supply transients while bias is applied. Use shielded signal and bias cables to minimize inductive pick-up. 0.150mm (0.005”) Thick Moly Tab 0.254mm (0.010”) Thick Alumina Thin Film Substrate Figure 2. General Handling: Handle the chip along the edges with a vacuum collet or with a sharp pair of bent tweezers. The surface of the chip has fragile air bridges and should not be touched with vacuum collet, tweezers, or fingers. Mounting The chip is back-metallized and can be die mounted with AuSn eutectic preforms or with electrically conductive epoxy. The mounting surface should be clean and flat. Eutectic Die Attach: A 80/20 gold tin preform is recommended with a work surface temperature of 255 deg. C and a tool temperature of 265 deg. C. When hot 90/10 nitrogen/hydrogen gas is applied, tool tip temperature should be 290 deg. C. DO NOT expose the chip to a temperature greater than 320 deg. C for more than 20 seconds. No more than 3 seconds of scrubbing should be required for attachment. Epoxy Die Attach: Apply a minimum amount of epoxy to the mounting surface so that a thin epoxy fillet is observed around the perimeter of the chip once it is placed into position. Cure epoxy per the manufacturer’s schedule. Wire Bonding Ball or wedge bond with 0.025mm (1 mil) diameter pure gold wire. Thermosonic wirebonding with a nominal stage temperature of 150 deg. C and a ball bonding force of 40 to 50 grams or wedge bonding force of 18 to 22 grams is recommended. Use the minimum level of ultrasonic energy to achieve reliable wirebonds. Wirebonds should be started on the chip and terminated on the package or substrate. All bonds should be as short as possible <0.31mm (12 mils). For price, delivery, and to place orders, please contact Hittite Microwave Corporation: 20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373 Order On-line at www.hittite.com 2-7