HMC173MS8 ATTENUATORS - SMT. GaAs MMIC VOLTAGE-VARIABLE ATTENUATOR, GHz. Features. Typical Applications. General Description

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1 v1.81 ATTENUATOR,.8 -. GHz Typical Applications The is ideal for.8 -. GHz Applications: Base Station Infrastructure Portable Wireless Features Single Positive Voltage Control: to +3V High Attenuation Range: GHz High P1 Compression Point: +16 m Ultra Small Package: MSOP Functional Diagram General Description The is an absorptive voltage variable attenuator in an 8-lead MSOP package. The device operates with a positive supply voltage and a positive control voltage. Unique features include a high dynamic attenuation range and excellent power handling performance through all attenuation states. The is ideal for operation in wireless applications between.8 GHz and 1.6 GHz. 1.7 to. GHz operation is possible, with a reduced maximum attenuation of 3 and increased VSWR. The can be used with an external driver circuit for improved linearity of attenuation. Electrical Specifications, T A = +5 C, = +4. Vdc, 5 Ohm System P arameter Min. T ypical Max. Units Insertion Loss (Min. Atten.) (VCTL =. Vdc).8-1. GHz GHz GHz Attenuation Range (VCTL = to +3 V).8-1. GHz GHz GHz Flatness (Peak to Peak).8-1. GHz GHz ±.15 ±.5 Return Loss (VCTL = to +3 V).8-1. GHz GHz GHz Input Power (.85 GHz) for.1 Compression Min Atten. Atten. > m m Input Power (.85 GHz) for 1. Compression Min Atten. Atten. > m m Input Third Order Intercept.85 GHz, Two-tone Input Power = +5. m Each Tone Min Atten. Atten. > m m Switching Characteristics trise, tfall (1/9% RF) ton, toff (5% CTL to 1/9% RF).8 -. GHz µs µs Elizabeth Drive, Chelmsford, MA 184 Phone: Fax:

2 v1.81 ATTENUATOR,.8 -. GHz Attenuation vs. Control and 1.9 GHz ATTENUATION () NORMALIZED ATTENUATION () GHz 1.9 GHz Attenuation vs. Temperature Normalized to +5 GHz C Input IP3 vs. Control GHz 85 MHz INPUT IP3 (m) Input P1 Compression@.85 GHz Test Condition (.85 GHz) C +5C Input Power For 1 Compression Point VCTL (Vdc) (Vdc) + 5C + 85C C Units Min. Attenuation m Max. Attenuation Worst Case Typical VCTL m m Broadband Attenuation and Insertion Loss Broadband Return Loss vs. Control Voltage ATTENUATION () FREQUENCY (GHz) -1 - INSERTION LOSS () RETURN LOSS () -5 V -1 V.5V -15 3V FREQUENCY (GHz) 1 Elizabeth Drive, Chelmsford, MA 184 Phone: Fax:

3 v1.81 ATTENUATOR,.8 -. GHz Typical Performance for.8-1. GHz Applications Attenuation vs. Control GHz ATTENUATION () C C Typical Performance for GHz Applications Attenuation vs. Control 1.9 GHz ATTENUATION () C +5C Return Loss vs. Control GHz RETURN LOSS () C and +5C Return Loss vs. Control 1.9 GHz RETURN LOSS () C C Elizabeth Drive, Chelmsford, MA 184 Phone: Fax:

4 v1.81 ATTENUATOR,.8 -. GHz Absolute Maximum Ratings Control and Bias Voltage V CTL Maximum Input Power = +4. Vdc -. Vdc to +8 Vdc +9 m +1 m Min. Attenuation Att. > V CTL to -1µA to +1µ A +4.Vdc +1µ A Storage Temperature Operating Temperature Outline Drawing 5 to +15 deg C to +85 deg C PIN 1 RF RF1 Gnd HMC /.1 (.95/ 3.5).116/.1.188/.196 (.95/ 3.5) (4.78/ 4.98) Gnd VCTL N/C N/C *Note: DC blocking capacitors are required for each RF port. Capacitor value determines lowest frequency of operation. XXXX YYWW LOT NUMBER DATE CODE YY= YEAR WW= WEEK PIN 1 (REF).38/.4 (.96/ 1.7).56 TYP (.65).3/.36 (.81/.91) to 5 deg.1 TYP (.3).1 MIN TYP (.53).5/.7 (.13/.18) 1. MATERIAL: A) PACKAGE BODY - LOW STRESS INJECTION - MOLDED PLASTIC, SILICA & SILICONE IMPREGNATED. B) LEADFRAME MATERIAL: COPPER ALLOY.. PLATING: LEAD-TIN SOLDER PLATE. 3. DIMENSIONS ARE IN INCHES (MILLIMETERS), UNLESS OTHERWISE SPECIFIED TOL. ARE ±.5 ( ±.13). 4. TAPE AND REEL SHIPMENT PACKAGING AVAILABLE, SEE PAGE Elizabeth Drive, Chelmsford, MA 184 Phone: Fax:

5 v1.81 ATTENUATOR,.8 -. GHz Attenuation Linearizing Control Circuit For The Voltage Variable Attenuator A driver circuit to improve the attenuation linearity of the can be implemented with a simple op-amp confi guration. A breakpoint linearization circuit will scale the voltage supplied to the control line of the, so that a more linear attenuation vs. control voltage slope can be achieved. A -5V and +5V supply is required. Diode and resistor values which defi ne the op-amp gain, and breakpoint were selected to optimize a measured production lot of attenuators at.85 GHz. R7 may be varied to optimize the performance of any given attenuator. If the input voltage to the linearizing circuit will not drop below 1.V, the R9 and D may be omitted, and this will greatly reduce the overall power consumption of the driver circuit. The linearizing circuit has been optimized for.85 GHz attenuation applicaitons. A similar approach may be used at other frequencies by adjusting R1 - R9 resistor values. Required Parts List Part AD8 R1 R R3 R4 R5 R6 R7 R8 Description Op-Amp Manufacturer Analog Devices 1K ohms K ohms 7.5K ohms 39K ohms K ohms 91K ohms 91 ohms 51 ohms Application Circuit VCTL IN R8 +5 R5 R7 R6-5V R U3 V+ AD8/AD V- _ 4 D1 R4-5V R 6 R3 R9 D +5V VCTL OUT R9 1 ohms D1, D LL4148 D-35 Digikey Return Loss vs. Control GHz -1 Attenuation vs. Control GHz RETURN LOSS () With Without ATTENUATION () With Without CONTROL VOLTAGE (Vdc) 1 3 CONTROL VOLTAGE (Vdc) Elizabeth Drive, Chelmsford, MA 184 Phone: Fax:

6 v1.81 ATTENUATOR,.8 -. GHz Evaluation Circuit Board The circuit board used in the fi nal application should use RF circuit design techniques. Signal lines should have 5 ohm impedance while the package ground leads should be connected directly to the ground plane similar to that shown. A suffi cient number of VIA holes should be used to connect the top and bottom ground planes. The evaluation circuit board as shown is available from Hittite Microwave Corporation upon request. Evaluation Circuit Board Layout Design Details L ayout Technique Grounded Co-Planar Waveguide (GCPW) Material FR4 D ielectric Thickness.8" (.71 mm) 5 Ohm Line Width.37" (.94 mm) G ap to Ground Edge.1" (.5 mm) G round VIA Hole Diameter.14" (.36 mm) C onnectors SMA-F (EF - Johnson P/N ) 1 Elizabeth Drive, Chelmsford, MA 184 Phone: Fax: