HMC424 v06.0809 ATTENUATORS - DIGITAL - CHIP 1 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz Typical Applications Features The HMC424 is ideal for: 0.5 dB LSB Steps to 31.5 dB • Fiber Optics & Broadband Telecom Single Control Line Per Bit • Microwave Radio & VSAT ±0.5 dB Typical Bit Error • Military Radios, Radar & ECM Die Size: 1.45 x 0.85 x 0.1 mm • Space Applications Functional Diagram General Description The HMC424 die is a broadband 6-bit GaAs IC digital attenuator MMIC chip. Covering DC to 13 GHz, the insertion loss is less then 4 dB typical. The attenuator bit values are 0.5 (LSB), 1, 2, 4, 8, and 16 dB for a total attenuation of 31.5 dB. Attenuation accuracy is excellent at ± 0.5 dB typical step error with an IIP3 of +32 dBm. Six control voltage inputs, toggled between 0 and -5V, are used to select each attenuation state. A single Vee bias of -5V allows operation at frequencies down to DC. Electrical Specifi cations, TA = +25° C, With Vee = -5V & VCTL = 0/-5V Parameter Frequency (GHz) Typ. Max. Units Insertion Loss DC - 8.0 GHz 8.0 - 13.0 GHz Min. 3.0 4.0 3.8 4.6 dB dB Attenuation Range DC - 13.0 GHz 31.5 dB Return Loss (RF1 & RF2, All Atten. States) DC - 8.0 GHz 8.0 - 13.0 GHz 12 15 dB dB 8 11 Attenuation Accuracy: (Referenced to Insertion Loss) 0.5 - 7.5 dB States 8 - 31.5 dB States Input Power for 0.1 dB Compression Input Third Order Intercept Point (Two-Tone Input Power= 0 dBm Each Tone) REF State All Other States Switching Characteristics ± 0.3 + 4% of Atten. Setting Max ± 0.3 + 6% of Atten. Setting Max dB dB 1.0 - 13.0 Ghz 22 dBm 1.0 - 13.0 Ghz 46 32 dBm dBm 30 50 ns ns DC - 13.0 GHz tRISE, tFALL (10/90% RF) tON/tOFF (50% CTL to 10/90% RF) 1-8 DC - 13.0 GHz DC - 13.0 GHz 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 HMC424 v06.0809 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz Return Loss RF1, RF2 0 -2 -5 -4 +25 C +85 C -55 C -6 -8 0.5 dB 1 dB 2 dB 4 dB 8 dB 16 dB 31.5 dB -10 -15 -20 -10 -25 0 3 6 9 12 15 0 3 6 FREQUENCY (GHz) 9 12 15 FREQUENCY (GHz) Normalized Attenuation (Only Major States are Shown) Bit Error vs. Attenuation State 2 -5 0.1 GHz 4 GHz 8 GHz 13 GHz 1 -10 BIT ERROR (dB) NORMALIZED ATTENUATION (dB) 0 -15 -20 0.5 dB 1 dB 2 dB 4 dB -25 8 dB 16 dB 31.5 dB 0 -1 -30 -35 -2 0 3 6 9 12 0 15 4 8 FREQUENCY (GHz) 12 16 20 24 28 32 ATTENUATION STATE (dB) Bit Error vs. Frequency Relative Phase vs. Frequency (Only Major States are Shown) (Only Major States are Shown) 2 100 0.5 dB 1 dB 2 dB 4 dB 8 dB 16 dB 31.5 dB 80 8 dB 16 dB 31.5 dB RELATIVE PHASE (deg) 0.5 dB 1 dB 2 dB 4 dB 1 BIT ERROR (dB) ATTENUATORS - DIGITAL - CHIP 0 RETURN LOSS (dB) INSERTION LOSS (dB) 1 (Only Major States are Shown) Insertion Loss 0 -1 60 40 20 0 -2 -20 0 3 6 9 FREQUENCY (GHz) 12 15 0 3 6 9 12 15 FREQUENCY (GHz) 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 1-9 HMC424 v06.0809 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz 1 Worst Case Step Error Between Successive Attenuation States Bias Voltage & Current Vee Range= -5 Vdc ± 10% 1.5 1 STEP ERROR (dB) ATTENUATORS - DIGITAL - CHIP 2 Vee (Vdc) Iee (Typ.) (mA) Iee (Max.) (mA) -5 2 5 0.5 0 -0.5 Control Voltage -1 -1.5 -2 0 3 6 9 12 15 State Bias Condition Low 0 to -3V @ 35 μA Typ. High Vee to Vee +0.8V @ 5 μA Typ. FREQUENCY (GHz) Truth Table Absolute Maximum Ratings Control Voltage Input V1 16 dB Low Low Low V2 8 dB Low Low Low V3 4 dB Low Low Low V4 2 dB Low Low Low V5 1 dB Low Low High V6 0.5 dB Low High Low Attenuation State RF1 - RF2 Reference I.L. 0.5 dB 1 dB Low Low Low High Low Low 2 dB Low Low High Low Low Low 4 dB Low High Low Low Low Low 8 dB High Low Low Low Low Low 16 dB High High High High High High 31.5 dB Any Combination of the above states will provide an attenuation approximately equal to the sum of the bits selected. Control Voltage (V1 to V6) Vee - 0.5 Vdc Bias Voltage (Vee) -7 Vdc Channel Temperature 150 °C Thermal Resistance 330 °C/W Storage Temperature -65 to + 150 °C Operating Temperature -55 to +85 °C RF Input Power (0.5 - 13 GHz) +25 dBm ELECTROSTATIC SENSITIVE DEVICE OBSERVE HANDLING PRECAUTIONS Die Packaging Information [1] Standard Alternate WP-8 (Waffle Pack) [2] [1] Refer to the “Packaging Information” section for die packaging dimensions. [2] For alternate packaging information contact Hittite Microwave Corporation. 1 - 10 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 HMC424 v06.0809 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz 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 ATTENUATORS - DIGITAL - CHIP 1 Outline Drawing Pad Descriptions Pad Number Function Description GND Die bottom must be connected to RF ground. 1, 3 RF1, RF2 This pad is DC coupled and matched to 50 Ohm. Blocking capacitors are required if RF line potential is not equal to 0V. 2 VEE Supply Voltage -5V ± 10% 4, 5, 6, 7, 8, 9 V1 - V6 See truth table and control voltage table. 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 1 - 11 HMC424 v06.0809 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz ATTENUATORS - DIGITAL - CHIP 1 1 - 12 Suggested Driver Circuit (One Circuit Required Per Bit Control Input) Simple driver using inexpensive standard logic ICs provides fast switching using minimum DC current. * Recommended value to suppress unwanted RF signals at V1 - V6 control lines. Assembly Diagram 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 HMC424 v06.0809 0.5dB LSB GaAs MMIC 6-BIT DIGITAL ATTENUATOR, DC - 13 GHz The die should be attached directly to the ground plane eutectically or with conductive epoxy (see HMC general Handling, Mounting, Bonding Note). 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. 0.102mm (0.004”) Thick GaAs MMIC Wire Bond 0.076mm (0.003”) Cleanliness: Handle the chips in a clean environment. DO NOT attempt to clean the chip using liquid cleaning systems. Static Sensitivity: strikes. 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. RF Ground Plane 0.150mm (0.005”) Thick Moly Tab ATTENUATORS - DIGITAL - CHIP 1 Mounting & Bonding Techniques for Millimeterwave GaAs MMICs 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 °C and a tool temperature of 265 °C. When hot 90/10 nitrogen/hydrogen gas is applied, tool tip temperature should be 290 °C. DO NOT expose the chip to a temperature greater than 320 °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 °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 1 - 13