RF3330 Preliminary 3 IF GAIN CONTROLLED AMPLIFIER Typical Applications • CATV Set-Top Boxes • Cable-Ready TVs • Cable Modems 3 0.15 0.05 1.59 1.61 0.365 TEXT* The RF3330 is a gain-controlled amplifier suitable for application in the IF receive section of a cable tuner. It consists of a high impedance differential input stage, a low impedance differential output stage, and a differential gain-controlled amplifier. The voltage gain may be varied by applying an analog control voltage. The device is fabricated on an advanced Bi-CMOS process, and is housed in an eight-lead SOT23 package. LINEAR CATV AMPLIFIERS Product Description 2.80 3.00 0.650 2.60 3.00 1.44 1.04 *When Pin 1 is in upper left, text reads downward (as shown). 0.127 3°MAX 0°MIN 0.35 0.55 Optimum Technology Matching® Applied Si BJT üSi Bi-CMOS GaAs HBT GaAs MESFET SiGe HBT Si CMOS Package Style: SOT23-8 Features • Single 5V Positive Power Supply • 26dB Gain Range • 150MHz Bandwidth VCC 1 GND 2 VOUT 3 VOUTB 4 Biasing & AGC Control 8 VCC • Compact Package 7 VIN 6 VINB 5 VAGC Ordering Information RF3330 RF3330 PCBA RF3330 PCBA Functional Block Diagram Rev A2 010820 IF Gain Controlled Amplifier Fully Assembled Evaluation Board - 75Ω Fully Assembled Evaluation Board - 50Ω RF Micro Devices, Inc. 7628 Thorndike Road Greensboro, NC 27409, USA Tel (336) 664 1233 Fax (336) 664 0454 http://www.rfmd.com 3-1 RF3330 Preliminary Absolute Maximum Ratings Parameter Supply Voltage Operating Ambient Temperature Storage Temperature Parameter 3 Rating Unit 7 -40 to +85 -60 to +150 V °C °C Specification Min. Typ. Max. Caution! ESD sensitive device. RF Micro Devices believes the furnished information is correct and accurate at the time of this printing. However, RF Micro Devices reserves the right to make changes to its products without notice. RF Micro Devices does not assume responsibility for the use of the described product(s). Unit Typical performance is at TA =+25°C, VCC =5V. Overall LINEAR CATV AMPLIFIERS Condition DC Specifications Supply Voltage Supply Current AGC Control Voltage 4.75 5.0 18 0.5 AGC Input Impedance 5.25 25 3.3 V mA V 10 MΩ 150 MHz 0.5V=Minimum Gain 3.3V=Maximum Gain AC Specifications 3dB Bandwidth Voltage Gain Maximum Minimum Maximum Input Level Maximum Output Level Output 1dB Compression Output Harmonic Distortion Input IP3, Maximum Gain Input IP3, Minimum Gain Input Noise, Maximum Gain Input Noise, Minimum Gain Output Impedance Input Impedance Output Load Impedance Output Load Capacitance 3-2 33.0 34.0 8.0 66 -44 45 60 4.5 42 10 2000 10.0 50 50 -40 1 2 dB dB dBmV(rms) dBmV(rms) dBmV(rms) dBc dBmV(rms) dBmV(rms) nV/rtHz nV/rtHz Ω Ω kΩ pF VAGC =3.3V VAGC =0.5V While meeting distortion specification While meeting distortion specification Maximum Gain Output level=50dBmV(rms); VAGC =3.3V Output level=50dBmV(rms); VAGC =3.3V Output level=50dBmV(rms); VAGC =0.5V Differential Differential Differential Differential Rev A2 010820 RF3330 Preliminary Pin 1 2 3 Function VCC GND VOUT Description Interface Schematic Supply Voltage Supply Ground Output pin. OUT OUTB 4 VOUTB Complementary output pin. OUT OUTB 5 VAGC AGC control voltage. 100 kΩ 10 kΩ VAGC 6 VINB VREF Complementary input pin. This should be externally AC-coupled to signal source. 1 kΩ VBIAS 1 kΩ VBIAS 75 IN 7 VIN INB Input pin. This should be externally AC-coupled to signal source. 1 kΩ VBIAS IN 8 VCC Rev A2 010820 1 kΩ 75 VBIAS INB Supply Voltage 3-3 LINEAR CATV AMPLIFIERS 3 RF3330 Preliminary Pin Out LINEAR CATV AMPLIFIERS 3 VCC 1 8 VCC GND 2 7 VIN VOUT 3 6 VINB VOUTB 4 5 VAGC Application Schematic VCC 100 pF 8 Biasing & AGC Control 3.3µF + 1 VIN 7 2 VINB 6 3 VOUT VAGC 5 4 VOUTB Note orientation of board. 3-4 Rev A2 010820 RF3330 Preliminary Evaluation Board Schematic (Download Bill of Materials from www.rfmd.com.) P1 P1-3 C2 100 nF 50 Ω µstrip J3 VIN 50 Ω µstrip C7 100 nF 50 Ω µstrip C8 100 nF (BAL) J1 VIN F1* 7 (BAL) (UNBAL) GND 3 AGC 4 GND 3 C1 100 pF C9 100 pF 8 J2 VIN VCC 2 HEADER4 VCC + C3 3.3 µF 1 Biasing & AGC Control R1* DNI 1 2 6 3 5 4 C4* DNI R2 470 Ω R4 470 Ω 50 Ω µstrip R3 51 Ω 6 1 J5 VOUT 5 2 (BAL) 4 3 T1 TTWB 1010-1 Note orientation of board. 50 Ω µstrip 3330410- AGC R6 5.1 kΩ C6 33 nF R5* DNI C5* DNI J4 VOUT (UNBAL) NOTES: 1. C3, Tantulum Capacitor: Case Size Y, 6.3 V. 2. See Evaluation Test Procedure for more information. 3. Parts with * following the reference designator should not be populated on the evaluation board. Rev A2 010820 3-5 LINEAR CATV AMPLIFIERS P1-1 RF3330 Preliminary Evaluation Board Layout Board Size 2.0” x 2.0” Board Thickness 0.062”, Board Material FR-4 LINEAR CATV AMPLIFIERS 3 3-6 Rev A2 010820 RF3330 Preliminary Evaluation Test Procedure Evaluation Board The 3330410 board has been designed to achieve maximum versatility for device evaluation. The board is designed for either a differential or single-ended input signal. Likewise, the output can be either singly or differentially loaded. There is also a separate VCC and AGC voltage pin. For constant maximum gain applications, the VCC and AGC pins can be tied together. Input For differential operation on the input, the J1 connector (VIN unbalanced) is not required. Differential voltages are applied directly through connectors J2 and J3 (VIN balanced). DC blocking capacitors are also provided to protect equipment or upstream components. Boards ordered from RF Micro Devices are assembled in this configuration. Single-ended operation on the input can be accomplished in two ways. The first option uses the differential board setup as described above, with the addition of an external low frequency 180° power combiner. The combiner splits the single input signal into two signals with inverted phase. The second option for singleended operation utilizes a SAW filter which converts from double to single-ended. The current evaluation board has an option to insert a SAW filter on the input. For this setup, the J1 connector (VIN unbalanced) would be utilized. The 3330410 board has been evaluated using a 44MHz Siemens+Matsushita filter. This is a common IF frequency used in cable modem applications. Output For differential operation on the output, the optional C4, C5, R1, and R5 would be inserted and the T1 transformer would be removed. The J4 (VOUT unbalanced) and J5 (VOUT balanced) connectors would be uses as differential outputs. For single-ended operation on the output, only the J4 connector (VOUT unbalanced) is used and only one analyzer is necessary. There is a 1:1 transformer to convert the unbalanced output to a balanced signal. The amplifier is designed to drive a 1000Ω load. Driving a 50Ω load, presented by the spectrum analyzer will cause the amplifier to saturate. In order to present a 1000Ω load to the amplifier a resistive matching circuit is on the board. Boards ordered from RF Micro Devices are assembled in this configuration. Test Setup Calibration Because of the fact that the impedances of the amplifier are not 50Ω, there are some special considerations when calibrating a test setup.The evaluation test setup is shown in Figure 1. Input As stated previously, the balanced input impedance of the RF3330 is 2000Ω. The signal generator used has an unbalanced 50Ω source, and is typically used in unbalanced 50Ω impedance systems. Due to this load mismatch, a positive amplitude offset needs to be applied to the signal generator. The formulas used to calculate this offset are given below in Equations 1 through 3. It should be noted that the unbalanced 1000Ω load is used, because all data in the datasheet is referenced to single-ended operation. Using a spectrum analyzer probe, the actual offset measured was 7.5dB, and this is what is used for the amplitude offset in the signal generator. Mismatch Loss (ML)=-10*log(1-|ΓL|2) ΓL =(Z-Z0)/(Z+Z0) Eq. 1 Eq. 2 ML=-10*log(1-[(1000-50)/(1000+50)]2)=7.4dB Eq. 3 Table 1. SAW Filters EPCOS P/N X6857D X6966M X6964D X6855M X6866D X6965M Rev A2 010820 FC (MHz) 36.000 36.125 43.750 44.000 44.000 44.000 3-7 3 LINEAR CATV AMPLIFIERS Introduction The RF3330 is an IF amplifier with AGC, designed for use in Cable Television applications. Voltage gain is varied using an analog voltage control signal. The differential input is high impedance (2000Ω) and the differential output is low impedance (10Ω). The 3dB bandwidth is 150MHz and has a maximum voltage gain of 34dB and a minimum voltage gain of 8dB. The AGC Control Voltage ranges from 0.5V for minimum gain to 3.3V for maximum gain. The device is packaged in the SOT23-8, which minimizes board area. RF3330 Preliminary Output On the output, the losses due to the resistive matching pad must also be calibrated out of the setup. Because of the 1:1 transformer, the spectrum analyzer appears as a 50Ω resistor in parallel with this circuit (see Figure 2). Equation 4 illustrates the calculation necessary to obtain the amount of loss due to this matching circuit. The balun also has an additional 0.5dB to 1.0dB of loss, which is added in to the overall output losses. This was verified with a spectrum analyzer probe. The offset used in the test setup is 32.5dB on the spectrum analyzer. Resistive Pad Loss= 20*log(25/(470+25+470))=-31.7dB Eq. 4 LINEAR CATV AMPLIFIERS 3 Frequency = 1 MHz to 150 MHz Frequency = 1 MHz to 150 MHz Signal Generator Mini-Circuits ZMSCJ-2-1 Divider RF3330 Resistive Match 1:1 Transformer Frequency = 1 MHz to 150 MHz Spectrum Analyzer 3330410 Evaluation Board Figure 1. RF3330 Test Setup R4 470 Ω R3 51 Ω 50 Ω R2 470 Ω Figure 2. Equivalent Output Circuit 3-8 Rev A2 010820 RF3330 Preliminary IIP3 versus Gain VCC=5.0V, F=50MHz 65.0 Gain versus VGC VCC=5.0V, F=50MHz 40.0 -40°C -40°C +25°C 35.0 +25°C 60.0 +85°C +85°C 30.0 Gain (dB) 3 IIP3 (dBmV) 55.0 50.0 25.0 20.0 45.0 LINEAR CATV AMPLIFIERS 15.0 40.0 10.0 35.0 5.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 Gain (dB) 0.5 1.0 1.5 2.0 2.5 3.0 3.5 VGC (V) IIP3 versus VGC VCC=5.0V, F=50MHz 65.0 -40°C +25°C IIP3 (dBmV) 60.0 +85°C 55.0 50.0 45.0 40.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 VGC (V) 3-9 Rev A2 010820 RF3330 Preliminary LINEAR CATV AMPLIFIERS 3 3-10 Rev A2 010820