ARA05050 Reverse Amplifier with Step Attenuator Data Sheet - Rev 2.7 features * Low Cost Integrated Monolothic GaAs Amplifier With Step Attenuator * Attenuation Range: 0-30 dB, Adjustable In 2dB Increments Via a 4 Wire Parallel Control * Meets DOCSIS Distortion Requirements at +58dBmV Output Signal Level * Low Distortion and Low Noise * Low Signal toNoise Ratio at All Gain Levels * Frequency Range: 5-100 MHz * 5 Volt Operation * RoHS-Compliant Package Option Applications S12 Package 28 Pin SSOP with Heat Slug * MCNS/DOCSIS Compliant Cable Modems * CATV Interactive Set-Top Box * OpenCable Set-Top Box * Fiber Nodes * Cable Modem Termination Systems (CMTS) product description The ARA05050 is a GaAs IC designed to provide the reverse path amplification and output level control functions in a CATV Set-Top Box or Cable Modem. It incorporates a digitally controlled precision step attenuator that is preceded by an ultra low noise amplifier stage, and followed by an ultra-linear output driver amplifier. This device is capable of meeting the MCNS/DOCSIS requirements for harmonic 4 Switch performance at a +58dBmV output level while requiring only a single polarity +5V supply. Both the input and the output are single-ended and matched to 75 Ohms. The precision attenuator provides up to 30 dB of attenuation in 2 dB increments. The ARA05050 is offered in a 28-pin SSOP package that features a heat slug on the bottom of the package, and is available in a RoHS-compliant option. Attenuation Control LPF ARA05050 Balun Upstream QPSK/16QAM Modulator RAM Clock Microcontroller with Ethernet MAC MAC Clock Diplexer Data Transmit Enable/Disable 5-42 MHz 54-860 MHz DoubleConversion Tuner 44 MHz SAW Filter QAM Receiver with FEC Data 10Base-T Transceiver Figure 1. Cable Modem or Set Top Box Application Diagram 04/2012 ROM RJ45 Connector ARA05050 RF OUT1 ATT IN ATT OUT RF IN2 30 dB, 2dBstep digital attenuator section RF IN A1 A2 ISET1 16 dB 8 dB 4 dB 2 dB ISET2 Figure 2: Functional Block Diagram 1 N/C N/C 28 2 Bypass N/C 27 3 ATTIN ATTOUT 26 4 RF OUT1 ISET2 25 5 VREF1 RFIN2 24 6 ATTACG1 ATTACG2 23 7 ATTACG1 ATTACG2 22 8 ATTACG1 ATTACG2 21 9 ATTACG1 ATTACG2 20 10 RF IN VREF2 19 11 ISET1 RF OUT2 18 12 VATT GND 17 13 16 dB 2 dB 16 14 8 dB 4 dB 15 Figure 3: Pinout 2 Data Sheet - Rev 2.7 04/2012 RF OUT2 ARA05050 Table 1: Pin Description PIN NAME 1 N/C 2 Bypass 3 ATTIN 4 PIN NAME No Connection(1) 28 N/C No Connection (1) Internal Bypass 27 N/C No Connection (1) Attenuator Input(2) 26 ATTOUT RFOUT1 Amplifier A1 Output and Supply 25 ISET2 Amplifier A2 Current Adjust (4) 5 VREF1 Reference Voltage for Amplifier A1 24 RFIN2 Amplifier A2 Input (4) 6 ATTACG1 Attenuator AC Ground 1(3) 23 ATTACG2 Attenuator AC Ground 2 (3) ATTACG1 Attenuator AC Ground 1(3) 22 ATTACG2 Attenuator AC Ground 2 (3) 8 ATTACG1 Attenuator AC Ground 1(3) 21 ATTACG2 Attenuator AC Ground 2 (3) 9 ATTACG1 Attenuator AC Ground 1(3) 20 ATTACG2 Attenuator AC Ground 2 (3) 10 RFIN Amplifier A1 Input(4) 19 VREF2 11 ISET1 Amplifier A1 Current Adjust(4) 18 RFOUT2 12 VATT Attenuator Supply 17 GND Ground 13 16 dB 16 dB Attenution Control Bit 16 2 dB 2 dB Attenuition Control Bit 14 8 dB 8 dB Attenution Control Bit 15 4 dB 4 dB Attenuition Control Bit 7 DESCRIPTION DESCRIPTION Attenuator Output (2) Reference Voltage for Amplifier A2 Amplifier A2 Output and Supply Notes: (1) All N/C pins should be grounded. (2) Pins should be AC-coupled. No external DC bias should be applied. (3) Pins should be AC-grounded. No external DC bias should be applied. (4) Pins should be grounded or pulled to ground through a resistor. No external DC bias should be applied. 3 Data Sheet - Rev 2.7 04/2012 ARA05050 electrical characteristics Table 2: Absolute Minimum and Maximum Ratings PARAMETER MIN MAX UNIT 0 9 VDC Amplifier Reference Voltages (pins 5, 19) -2.5 VSUP 2 VDC RF Power at Amplifier Inputs (pins 10, 24) - +60 dBmV Attenuator Controls (pins 13, 14, 15, 16) 0 6 V -55 +200 C Soldering Temperature - 260 C Soldering Time - 5 Sec Analog Supply: VSUP (pins 4, 12, 18) Storage Temperature Stresses in excess of the absolute ratings may cause permanent damage. Functional operation is not implied under these conditions. Exposure to absolute ratings for extended periods of time may adversely affect reliability. Notes: 1. Pins 3 and 26 should be AC-coupled. No external DC bias should be applied. 2. Pins 10, 11, 24 and 25 should be grounded or pulled to ground through a resistor. No external DC bias should be applied. 3. Pins 6, 7, 8, 9, 20, 21, 22 and 23 should be AC-grounded. No external DC bias should be applied. Table 3: Operating Ranges PARAMETER MIN TYP MAX UNIT Amplifier Supply: VDD (pins 4, 18) 4.5 5 7 VDC Attenuator Supply: VATTN (pin 12) - 5 7 VDC Attenuator Controls (pins 13, 14, 15, 16) 0 - 5.5 V Amplifier Reference Voltages (pins 5, 19) - 1.75 - VDC Output Switch Control (pin 25) 0 - 5.5 V -40 25 85 C Case Temperature The device may be operated safely over these conditions; however, parametric performance is guaranteed only over the conditions defined in the electrical specifications. 4 Data Sheet - Rev 2.7 04/2012 ARA05050 Table 4: DC Electrical Specifications TA=25C; VDD, Vattn = +5.0 VDC PARAMETER MIN TYP MAX UNIT Amplifier A1 Current (pin 4) - 75 95 mA Amplifier A2 Current (pin 18) - 100 130 mA Attenuator Current (pin 12) - 8 - mA Total Power Consumption - 0.92 1.2 W Thermal Resistance (JC) - 36 - C/W COMMENTS Table 5: AC Electrical Specifications TA=25C; VDD, Vattn = +5.0 VDC PARAMETER MIN TYP MAX UNIT Gain (10 MHz) 31 32 33 dB 0 dB attenuation setting Gain Flatness - 0.75 1.5 dB 5 to 100 MHz Gain Variation over Temperature - -0.006 - dB/C 1.6 3.8 8.0 16.0 1.85 4.0 8.3 16.6 2.2 4.2 8.5 17.0 2nd Harmonic Distortion Level 5 MHz 25 MHz - -60 -63 3rd Harmonic Distortion Level 5 MHz 25 MHz - Attenuation Steps 2 dB 4 dB 8 dB 16 dB dB 5 to 42 MHz (1), Monotonic -55 -55 dBc +58 dBmV into 75 Ohms -63 -63 -60 -60 dBc +58 dBmV into 75 Ohms 78 - - dBmV 1 dB Gain Compression Point - 70 - dBmV Noise Figure - 1.7 2.5 dB 3rd Order Output Intercept Notes: (1) See Figures 5 and 6 for performance at higher frequencies. All specifications as measured in ANADIGICS test fixture. 5 COMMENTS Data Sheet - Rev 2.7 04/2012 ARA05050 continued: AC Electrical Specifications TA=25C; VDD, Vattn = +5.0 VDC MIN TYP MAX UNIT COMMENTS Output Noise Power Active/No Signal/Min. Atten. Set. Active/No Signal/Max. Atten. Set. - - - dBmV Any 160 kHz bandwidth from 5 to 42 MHz Input Impedance - -75 - Ohms Input Return Loss - -20 -15 dB Output Impedance - 75 - Ohms Output Return Loss - -20 -15 dB PARAMETER 75 system 75 system Note: As measured in ANADIGICS test fixture Table 6: Logic Interface Specifications TA=25C; VDD, Vattn = +5.0 VDC PARAMETER MIN TYP MAX UNIT Attenuator Control Logic VIN,LOW VIN,HIGH 0 2.8 - 0.5 5.5 V - 5K - Ohms Attenuator Control Impedance COMMENTS Bypasses atten. stage Enables atten. stage Note: (1) Specification applies when 470 Ohm resistor is connected from pin 2 to ground (see test circuit in Figure 4). Table 7: Attenuator Logic ATTENUATION (dB) 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 2 dB Logic Input (pin 16) L H L H L H L H L H L H L H L H 4 dB Logic Input (pin 15) L L H H L L H H L L H H L L H H 8 dB Logic Input (pin 14) L L L L H H H H L L L L H H H H 16 dB Logic Input (pin 13) L L L L L L L L H H H H H H H H Note: "L" = logic low, "H" = logic high 6 Data Sheet - Rev 2.7 04/2012 Figure 4: Test Circuit Data Sheet - Rev 2.7 04/2012 1uF 0.1uF +5 V 0.01uF 0.8pF 0.1pF 620 Ohms 0.01uF 5K Ohms 0.1uF 1uF 0.01uF 0.1uF 470 Ohms (see note) OUT1 IN ACG1 ACG1 ACG1 ACG1 IN 8 dB 16 dB V ATTN ISET1 RF ATT ATT ATT ATT V REF1 RF ATT Bypass N/C ARA05050 VG1 (Not Used) 5K Ohms 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Note: The 470 Ohm resistor from pin 2 to ground is installed for 3V attenuator control logic levels. For 5V logic, the 470 Ohm resistor is removed. 3.9 Ohms RF Input (75 Ohms) 20 Ohms 0.1uF 8 dB 1.8K Ohms 1000pF 10uH 0.01uF 1uF 1 6 dB 7 OUT IN2 ACG2 ACG2 ACG2 ACG2 OUT2 4 dB 2 dB GND RF V REF2 ATT ATT ATT ATT RF I SET2 ATT N/C N/C 15 16 17 18 19 20 21 22 23 24 25 26 27 28 20 Ohms 1uF 0.01uF 0.1uF 2 dB 3.3K Ohms +5 V +5 V 10uH 1uF 1uF 0.01uF 3.3K Ohms 0.1uF 0.01 uF 5K Ohms 1.8K Ohms 620 Ohms 0.1 uF 5K Ohms VG2 (Not Used) RF Output (75 Ohms) ARA05050 4 dB ARA05050 performance data 8 Figure 5: S21 (0 - 16 dB Attenuation) Figure 6: S21 (16 - 30 dB Attenuation) Figure 7: S11 - Log Scale Figure 8: S22 - Log Scale Figure 9: S11 - Smith Chart Figure 10: S22 - Smith Chart Data Sheet - Rev 2.7 04/2012 ARA05050 Figure 11: Attenuator Switching Speed - 16 dB Step Figure 12: Harmonic Performance 9 Data Sheet - Rev 2.7 04/2012 ARA05050 application information Printed Circuit Board Layout Considerations The ARA05050 is a high-performance RF device. Special consideration must be given to certain features of the the printed circuit board layout, as they can affect the RF performance of the IC. Refer to the ANADIGICS application note "CATV Reverse Amp w/ Step Attenuator" for more details. Thermal Layout Considerations The device package for the ARA05050 features a heat slug on the bottom of the package body. Use of the heat slug is an integral part of the device design. Soldering it to the ground plane of the PC board will ensure the lowest possible thermal resistance for the device, and will result in the longest MTF (mean time to failure.) Amplifier Enable / Disable The ARA05050 includes two amplification stages that each can be shut down through external control pins Vref1 and Vref2 (pins 5 and 19, respectively.) By applying a typical bias of 1.75 Volts to these pins, the amplifiers are enabled. In order to fully disable an amplifier, its control pin requires a negative bias of -1.5 to -2.0 Volts. A PC board layout that optimizes the benefits of the heat slug is shown in Figure 13. The via holes located under the body of the device must be plated through to a ground plane layer of metal, in order to provide sufficient thermal conductivity. The recommended solder mask outline is shown in Figure 14. Amplifier Bias Current The Iset pins (11 and 25) set the bias current for the amplification stages. Grounding these pins results in the maximum possible current. By placing a resistor from the pin to ground, the current can be reduced. The recommended bias conditions use the configuration shown in the test circuit schematic in Figure 4. 0.025BSC ESD Sensitivity Electrostatic discharges can cause permanent damage to this device. Electrostatic charges accumulate on test equipment and the human body, and can discharge without detection. Proper precautions and handling are strongly recommended. Refer to the ANADIGICS application note on ESD precautions. 0.089 0.014TYP BODY OUTLINE (NOMINAL ) 0.025MIN. 0.163 0.099 0.070 0.1520.150 REF. 0.197 0.060TYP. 0.386REF. 0.400 Figure 13: PC Board Layout 10 Data Sheet - Rev 2.7 04/2012 (12X)0.020 TO 0.060DIA.P PLATED THRU HOLES. ARA05050 0.016TYP. 0.091 0.053 0.025TYP. 0.163 0.242 0.085 0.098 0.025BSC 0.145 DIMENSIONSARE IN INCHES Figure 14: Solder Mask Outline 11 Data Sheet - Rev 2.7 04/2012 ARA05050 PACKAGE OUTLINE Figure 15: S12 Package Outline - 28 Pin SSOP with Heat Slug 12 Data Sheet - Rev 2.7 04/2012 ARA05050 COMPONENT PACKAGING Volume quantities of the ARA05050 are supplied on tape and reel. Each reel holds 3,500 pieces. Smaller quantities are available in plastic tubes of 50 pieces. Figure 16: Reel Dimensions Figure 17: Tape Dimensions 13 Data Sheet - Rev 2.7 04/2012 ARA05050 Ordering Information ORDER NUMBER TEMPERATURE RANGE PACKAGE DESCRIPTION ARA05050S12CTR -40 to 85 0C 28 Pin SSOP with Heat Slug 3,500 piece tape and reel ARA05050S12C -40 to 85 0C 28 Pin SSOP with Heat Slug Plastic tubes (50 pieces per tube) ARA05050RS12P1 -40 to 85 0C RoHS-compliant 28 Pin SSOP with Heat Slug COMPONENT PACKAGING 3,500 piece tape and reel ANADIGICS, Inc. 141 Mount Bethel Road Warren, New Jersey 07059, U.S.A. Tel: +1 (908) 668-5000 Fax: +1 (908) 668-5132 URL: http://www.anadigics.com E-mail: Mktg@anadigics.com IMPORTANT NOTICE ANADIGICS, Inc. reserves the right to make changes to its products or to discontinue any product at any time without notice. The product specifications contained in Advanced Product Information sheets and Preliminary Data Sheets are subject to change prior to a product's formal introduction. Information in Data Sheets have been carefully checked and are assumed to be reliable; however, ANADIGICS assumes no responsibilities for inaccuracies. ANADIGICS strongly urges customers to verify that the information they are using is current before placing orders. warning ANADIGICS products are not intended for use in life support appliances, devices or systems. Use of an ANADIGICS product in any such application without written consent is prohibited. 14 Data Sheet - Rev 2.7 04/2012