HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 GHz ATTENUATORS - DIGITAL - CHIP 1 Typical Applications Features The HMC425 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: 1.5 x 0.85 x 0.1 mm • Space Applications General Description Functional Diagram The HMC425 die is a broadband 6-bit GaAs IC digital attenuator MMIC chip. Covering 2.4 to 8 GHz, the insertion loss is less then 3.5 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 +40 dBm. Six control voltage inputs, toggled between 0 and +3 to +5V, are used to select each attenuation state. A single Vdd bias of +3 to +5V is required. Electrical Specifi cations, TA = +25° C, With Vdd = +5V & Vctl = 0/+5V (Unless Otherwise Noted) Parameter Frequency (GHz) Insertion Loss 2.4 - 6.0 GHz 6.0 - 8.0 GHz Attenuation Range 2.4 - 8.0 GHz Return Loss (RF1 & RF2, All Atten. States) 2.4 - 8.0 GHz Attenuation Accuracy: (Referenced to Insertion Loss) Input Power for 0.1 dB Compression Input Third Order Intercept Point (Two-Tone Input Power= 0 dBm Each Tone) All States Vdd= 5V Vdd= 3V REF - 16.0 dB States 16.5 - 31.5 dB States Switching Characteristics 12 Typ. Max. Units 2.7 3.5 3.2 4.0 dB dB 31.5 dB 15 dB ± 0.4 + 4% of Atten. Setting Max dB 2.4 - 8.0 GHz 22 19 dBm dBm 2.4 - 8.0 GHz 45 35 dBm dBm 160 180 ns ns 2.4 - 8.0 GHz tRISE, tFALL (10/90% RF) tON/tOFF (50% CTL to 10/90% RF) 1 - 14 2.4 - 8.0 GHz Min. 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 HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 GHz (Only Major States are Shown) 0 -2 -5 RETURN LOSS (dB) INSERTION LOSS (dB) 0 -4 +25 C +85 C -55 C -6 -8 0.5 dB 1 dB 2 dB 4 dB -10 8 dB 16 dB 31.5 dB -15 -20 -10 -25 1 2 3 4 5 6 7 8 9 10 1 2 3 4 FREQUENCY (GHz) 5 6 7 8 9 10 28 32 9 10 FREQUENCY (GHz) Normalized Attenuation (Only Major States are Shown) Bit Error vs. Attenuation State 2 2.4 GHz 3.5 GHz 5.5 GHz 8.0 GHz -5 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 -2 -35 1 2 3 4 5 6 7 8 9 0 10 4 8 12 16 20 24 ATTENUATION STATE (dB) FREQUENCY (GHz) Bit Error vs. Frequency Relative Phase vs. Frequency (Only Major States are Shown) (Only Major States are Shown) 2 80 8 dB 16 dB 31.5 dB 0.5 dB 1 dB 2 dB 4 dB 8 dB 16 dB 31.5 dB 60 RELATIVE PHASE (deg) 0.5 dB 1 dB 2 dB 4 dB 1 BIT ERROR (dB) ATTENUATORS - DIGITAL - CHIP 1 Return Loss RF1, RF2 Insertion Loss 0 -1 40 20 0 -20 -2 -40 1 2 3 4 5 6 7 FREQUENCY (GHz) 8 9 10 1 2 3 4 5 6 7 8 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 - 15 HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 GHz 1 Worst Case Step Error Between Successive Attenuation States Bias Voltage & Current Vdd Range= +3 to +5 Vdc 1.5 STEP ERROR (dB) ATTENUATORS - DIGITAL - CHIP 2 Idd (Typ.) (μA) Vdd (Vdc) 1 0.5 +3.0 10 +5.0 30 0 -0.5 Control Voltage -1 -1.5 State Bias Condition -2 Low 0 to 0.2V @ 10 μA Typ. High Vdd ± 0.2V @ 5 μA Typ. 1 2 3 4 5 6 7 8 9 10 FREQUENCY (GHz) Note: Vdd= +3V to +5V Truth Table Absolute Maximum Ratings Control Voltage Input V1 16 dB High V2 8 dB High V3 4 dB High V4 2 dB High V5 1 dB High V6 0.5 dB High Attenuation State RF1 - RF2 Reference I.L. High High High High High Low 0.5 dB High High High High Low High 1 dB High High High Low High High 2 dB High High Low High High High 4 dB High Low High High High High 8 dB Low High High High High High 16 dB Low Low Low Low Low Low 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) Vdd +0.5 Vdc Bias Voltage (Vdd) +7.0 Vdc Storage Temperature -65 to + 150 °C Operating Temperature -55 to +85 °C RF Input Power (2.4 - 8.0 GHz) +30 dBm ESD Sensitivity (HBM) Class 1A 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 - 16 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 HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 GHz 1 ATTENUATORS - DIGITAL - CHIP Outline Drawing 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 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. 2 Vdd Supply Voltage 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 - 17 HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 GHz Assembly Diagram ATTENUATORS - DIGITAL - CHIP 1 1 - 18 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 HMC425 v02.0907 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL POSITIVE CONTROL ATTENUATOR, 2.4 - 8.0 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. 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”) 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 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 - 19