ARA2005

ARA2005 Reverse Amplifier with Step Attenuator FEATURES · · · · · · · · · · · · PRELIMINARY DATA SHEET - Rev 1.3 Low cost integrated monolithic GaAs amplifier with step attenuator Attenuation Range: 0-58 dB, adjustable in 4dB increments via a 4 wire parallel control Meets DOCSIS distortion requirements at a +60dBmV output signal level Low distortion and low noise Frequency range: 5-100MHz 5 Volt operation -40 to +85 0C temperature range MCNS/DOCSIS Compliant Cable Modems CATV Interactive Set-Top Box Telephony over Cable Systems OpenCable Set-Top Box Residential Gateway APPLICATIONS S8 Package 28 Pin SSOP PRODUCT DESCRIPTION The ARA2005 is a monolithic GaAs device designed to provide the reverse path amplification and output level control functions in a Cable TV Set Top Box or Cable Modem. It incorporates a digitally controlled precision step attenuator, which is preceded by an ultra low noise amplifier stage and followed by an ulta-linear output driver amplifier. The ARA2005 uses a balanced circuit design that exceeds the MCNS/ DOCSIS requirement for harmonic performance at a +60 dBmV output level while requiring only a single 4 Attenuation Control +5V supply. Both the input and output of the device are matched to 75 Ohms with an appropriate transformer. The precision attenuator provides up to 58 dB of attenuation in 4 dB increments, programmable via a four-bit digital control interface. With external passive components, this device meets IEC 1000-4-12 and ANSI/IEEE C62.41-1991 100KHz ringwave tests, as well as IEC1000-4-5 1.2/50mS surge tests. The ARA2005 is offered in a 28-pin SSOP package. Balun ARA2005 Low Pass Filter Upstream QPSK/16QAM Modulator Clock Data RAM ROM 5-42 MHz Transmit Enable/Disable MAC Clock 44 MHz Data Microcontroller with Ethernet MAC Diplexer 54-860 MHz DoubleConversion Tuner SAW Filter QAM Receiver with FEC 10Base-T Transceiver RJ45 Connector Figure 1: Cable Modem or Set Top Box Application Diagram 08/2001 ARA2005 ATTIN (+) A1OUT (+) A1IN (+) 32 dB 16 dB 8 dB 4 dB ATTOUT (+) A2IN (+) A2OUT (+) ISET2 EFET ISET1 Vg1 A1IN (-) A1OUT (-) ATTIN (-) EFET Vg2 A2OUT (-) A2IN (-) ATTOUT (-) 32 dB 16 dB 8 dB 4 dB Figure 2: Functional Block Diagram 1 2 3 4 5 6 7 8 9 10 11 12 13 14 GND VATTN ATTIN (+) A1OUT (+) GND A1IN (+) Vg1 ISET1 A1IN (-) GND A1OUT (-) ATTIN (-) 32 dB 16 dB Figure 3: Pin Out GND GND ATTOUT (+) A2IN (+) GND A2OUT (+) Vg2 ISET2 A2OUT (-) GND A2IN (-) ATTOUT (-) 4 dB 8 dB 28 27 26 25 24 23 22 21 20 19 18 17 16 15 2 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 ARA2005 Table 1: Pin Description PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 N AME GND VATTN ATTIN (+) A1OUT (+) GND A1IN (+) V g1 ISET1 A1IN (-) GND A1OUT (-) ATTIN (-) 32 dB 16 dB D ESC R IPTION Ground Supply for Attenuator Attenuator Input (+) (1) Ampli fi er A1 (+) Output Ground Ampli fi er A1 (+) Input (1) PIN 15 16 17 18 19 20 21 22 23 24 25 26 27 28 N AME 8 dB 4 dB ATTOUT (-) A2IN (-) GND A2OUT (-) ISET2 V g2 A2OUT (+) GND A2IN (+) ATTOUT (+) GND GND D ESC R IPTION 8 dB Attenuati on C ontrol Bi t 4 dB Attenuati on C ontrol Bi t Attenuator (-) Output Ampli fi er A2 (-) Input Ground Ampli fi er A2 (-) Output Ampli fi er A2 (+/-) C urrent Adjust Ampli fi er A2 (+/-) C ontrol Ampli fi er A2 (+) Output Ground Ampli fi er A2 (+) Input Attenuator (+) Output Ground Ground (1) (1) (1) Ampli fi er A1 (+/-) C ontrol Ampli fi er A1 (+/-) C urrent Adjust Ampli fi er A1 (-) Input Ground Ampli fi er A1 (-) Output Attenuator Input (-) (1) (1) (1) 32 dB Attenuati on C ontrol Bi t 16 dB Attenuati on C ontrol Bi t Notes: (1) Pins should be AC-coupled. No external DC bias should be applied. PRELIMINARY DATA SHEET - Rev 1.3 08/2001 3 ARA2005 ELECTRICAL CHARACTERISTICS Table 2: Absolute Minimum and Maximum Ratings PAR AMETER Analog Supply (pi ns 2, 4, 11, 20, 23) Ampli fi er C ontrols Vg1, Vg2 (pi ns 7, 22) RF Power at Inputs (pi ns 6, 9) MIN 0 -5 0 -55 - MAX 9 2 +60 6 +200 260 5 U N IT VD C V dBmV V 0 Attenuator C ontrols (pi ns 13, 14, 15, 16) Storage Temperature Solderi ng Temperature Solderi ng Ti me C C 0 S ec 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, 6, 9, 12, 17, 18, 25 and 26 should be AC-coupled. No external DC bias should be applied. 2. Pins 8 and 21 should be grounded or pulled to ground through a resistor. No external DC bias should be applied. Table 3: Operating Ranges PAR AMETER Ampli fi er Supply: VDD (pi ns 4, 11, 20, 23) Attenuator Supply: VATTN (pi n 2) Attenuator C ontrols (pi ns 13, 14, 15, 16) Ampli fi er C ontrols Vg1, Vg2 (pi ns 7, 22) C ase Temperature MIN 4.5 VDD-0.5 0 -5 -40 TYP 5 5 1 25 MAX 7 7 VDD+0.5 2 85 U N IT VD C VD C V V 0 C The device may be operated safely over these conditions; however, parametric performance is guaranteed only over the conditions defined in the electrical specifications. 4 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 ARA2005 Table 4: DC Electrical Specifications TA=25°C; VDD, VATTN = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER Ampli fi er A1 C urrent (pi ns 4, 11) Ampli fi er A2 C urrent (pi ns 20, 23) Attenuator C urrent (pi n 2) Total Power C onsumpti on MIN - TYP 48 2.4 70 3.7 2 600 40 MAX 80 6 110 9 5 900 100 U N IT mA mA mA mW C OMMEN TS Tx enabled Tx di sabled Tx enabled Tx di sabled Tx enabled Tx di sabled Table 5: AC Electrical Specifications TA=25°C; VDD, VATTN = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER Gai n (10 MHz) Gai n Flatness Gai n Vari ati on over Temperature Attenuati on Steps 4 dB 8 dB 16 dB 32 dB MIN 27.5 3.6 7.5 15.0 30.2 56.3 78 - TYP 29.3 0.75 1.5 -0.006 3.75 7.75 15.4 30.75 57.8 -75 -60 68.5 3.0 MAX 30.5 4.0 8.0 15.8 31.3 59.1 -53 -53 4.0 U N IT dB dB dB/°C C OMMEN TS 0 dB attenuati on setti ng 5 to 42 MHz 5 to 65 MHz dB Monotoni c Maxi mum Attenuati on 2nd Harmoni c D i storti on Level (10 MHz) 3rd Harmoni c D i storti on Level (10 MHz) 3rd Order Output Intercept 1 dB Gai n C ompressi on Noi se Fi gure Note: As measured in ANADIGICS test fixture dB dB c dB c dBmV dBmV dB Includes i nput balun loss +60 dBmV i nto 75 Ohms +60 dBmV i nto 75 Ohms PRELIMINARY DATA SHEET - Rev 1.3 08/2001 5 ARA2005 continued: AC Electrical Specifications TA=25°C; VDD, VATTN = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER Output Noi se Power Acti ve / No Si gnal / Mi n. Atten. Set. Acti ve / No Si gnal / Max. Atten. Set. Isolati on i n Tx di sable mode D i fferenti al Input Impedance Input Impedance Input Return Loss (75 Ohm characteri sti c i mpedance) D i fferenti al Output Impedance Output Impedance Output Return Loss (75 Ohm characteri sti c i mpedance) Output Voltage Transi ent Tx enable / Tx di sable Note: As measured in ANADIGICS test fixture MIN - TYP 52 300 75 -20 -5 300 75 -17 -15 4 MAX -38.5 -53.8 -12 -12 -10 100 7 U N IT dBmV dB Ohms Ohms dB Ohms Ohms dB mVp-p C OMMEN TS Any 160 kHz bandwi dth from 5 to 42 MHz between pi ns 6 and 9 (Tx enabled) wi th transformer (Tx enabled) Tx enabled Tx di sabled between pi ns 20 and 23 wi th transformer Tx enabled Tx di sabled 0 dB attenuator setti ng 24 dB attenuator setti ng 6 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 Control A1 0 / +3 V +5 V Control A2 0 / +3 V +5 V 1uF 2K Ohms 2K Ohms 1K Ohms 0.1uF 2K Ohms 10uH 470pF 1000pF RF Input (75 Ohms) Turns Ratio 1:2 1.2K Ohms 1000pF 2 3 4 5 6 7 8 1 1uF 1K Ohms 0.1uF 32 dB 16 dB 8 dB +5 V 4 dB PRELIMINARY DATA SHEET - Rev 1.3 08/2001 GND VATTN ATTIN (+) A1OUT (+) GND A1IN (+) Vg1 ISET1 A1IN (-) GND A1OUT (-) ATTIN (-) 32 dB 16 dB ARA2005 GND GND 28 27 Figure 4: Test Circuit ATTOUT (+) 26 A2IN (+) GND A2OUT (+) Vg2 ISET2 A2OUT (-) GND A2IN (-) ATTOUT (-) 4 dB 8 dB 25 24 23 22 21 20 19 18 17 16 15 2K Ohms 470pF 470pF Turns Ratio 2:1 RF Output (75 Ohms) 1500pF 3.9 Ohms 9 10 1.2K Ohms 1000pF 1000pF 10uH 1uF 11 12 13 14 Toko Balun 616PT-1030 470pF 0.1uF Note: Tx Enable: Control A1 and Control A2 = +3V Tx Disable: Control A1 and Control A2 = 0V ARA2005 7 ARA2005 PERFORMANCE DATA Figure 5: Gain & Noise Figure vs Frequency Gain 35 30 25 Gain (dB) 20 15 10 5 10 30 50 Frequency (MHz) 70 90 Noise Figure 8 7 6 5 4 3 2 NF (dB) 6 5 3 2 Measured @ 30 MHz 20 3 4 5 VDD ( Volts ) 6 7 1 Figure 6: Gain & Noise Figure vs VDD 35 Gain Noise Figure 32 GAIN (dB) 26 23 Figure 7: Gain & Noise Figure vs Temperature 35 Gain Noise Figure 6 32 GAIN (dB) 5 26 3 23 Measured @ 30 MHz 20 -40 -25 -10 5 20 35 o 2 1 50 65 80 Temperature (C ) 8 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 NF (dB) 29 4 NF (dB) 29 4 ARA2005 Figure 8: Harmonic Distortion vs VDD POUT = 58dBmV 2nd Harmonic -20 -30 Harmonic Level (dBc) -40 -50 -60 -70 Measured @ 5 MHz -80 3 4 5 VDD ( Volts ) 6 7 3rd Harmonic Figure 9: Harmonic Distortion vs VDD POUT = 58dBmV 2nd Harmonic -20 -30 Harmonic Level (dBc) -40 -50 -60 -70 Measured @ 12 MHz -80 3 4 5 VDD ( Volts ) 6 7 3rd Harmonic Figure 10: Harmonic Distortion vs Temperature POUT = 58dBmV 2nd Harmonic -40 -45 Harmonic level (dBc) -50 -55 -60 -65 -70 -75 -80 -40 -25 -10 5 20 Measured @ 5 MHz 35 50 65 80 3rd Harmonic Temperature (Co) PRELIMINARY DATA SHEET - Rev 1.3 08/2001 9 ARA2005 Figure 11: Harmonic Distortion vs Power Out 2nd -30 -35 -40 Harmonics (dBc) -45 -50 -55 -60 -65 -70 -75 49 51 53 55 57 59 61 63 65 67 3rd Pout (dBmV) Figure 12: Transients vs Attenuation POUT = 55dBmV at 0dB attenuation DOCSIS 1.1 Spec. 100 90 80 Transient (mV) 70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 Power Attenuation (dB) ARA2005 ARA2001 Figure 13: Harmonic Performance over Frequency POUT = +62dBmV 2nd Harmonic -50 -52 Harmonic Level (dBc) -54 -56 -58 -60 -62 -64 -66 -68 -70 -72 0 5 10 15 20 Frequency (MHz) 25 30 35 40 3rd Harmonic 10 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 ARA2005 Figure 14: IIP2 & IIP3 vs Frequency IIP2 40 IIP3 14 36 IIP2 (dBm) 12 IIP3 (dBm) IIP3 (dBm) 32 10 28 8 24 Measured @ V DD = 5 Volts Pin = -20 dBm per tone 20 5 15 25 35 45 55 65 Frequency (MHz) 75 85 95 6 4 Figure 15: IIP2 & IIP3 vs VDD IIP2 40 IIP3 15 36 11 IIP2 (dBm) 32 7 28 3 24 Measured @ 65 MHz Two tones @ 29.5 MHz 20 3 4 5 VDD (Volts) 6 7 -1 -5 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 11 ARA2005 APPLICATION INFORMATION Transmit Enable / Disable The ARA2005 includes two amplification stages that each can be shut down through external control pins Vg1 and Vg2 (pins 7 and 22, respectively.) By applying a slightly positive bias of typically +1.0 Volts, the amplifier is enabled. In order to disable the amplifier, the control pin needs to be pulled to ground. A practical way to implement the necessary control is to use bias resistor networks similar to those shown in the test circuit schematic (Figure 4.) Each network includes a resistor shunted to ground that serves as a pull-down to disable the amplifier when no control voltage is applied. When a positive voltage is applied, the network acts as a voltage divider that presents the required +1.0 Volts to enable the amplifier. By selecting different resistor values for the voltage divider, the network can accommodate different control voltage inputs. The Vg1 and Vg2 pins may be connected together directly, and controlled through a single resistor network from a common control voltage. Amplifier Bias Current The ISET pins (8 and 21) 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. Attenuator Control Each of the four internal attenuation stages of the ARA2005 is controlled by a TTL-compatible logic input at one of the attenuator control pins (13 - 16). A logic high will enable a given attenuator stage, and a logic low will bypass it. Output Transformer Matching the output of the ARA2005 to a 75 Ohm load is accomplished using a 2:1 turns ratio transformer. In addition to providing an impedance transformation, this transformer provides the bias to the output amplifier stage via the center tap. The transformer also cancels even mode distortion products and common mode signals, such as the voltage transients that occur while enabling and disabling the amplifiers. As a result, care must be taken when selecting the transformer to be used at the output. It must be capable of handling the RF and DC power requirements without saturating the core, and it must have adequate isolation and good phase and amplitude balance. It also must operate over the desired frequency and temperature range for the intended application. 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. Although the ARA2005 has some built-in ESD protection, proper precautions and handling are strongly recommended. Refer to the ANADIGICS application note on ESD precautions. 12 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 ARA2005 PACKAGE OUTLINE Figure 16: S8 Package Outline - 28 Pin SSOP PRELIMINARY DATA SHEET - Rev 1.3 08/2001 13 ARA2005 COMPONENT PACKAGING Volume quantities of the ARA2005 are supplied on tape and reel. Each reel holds 3,500 pieces. Smaller quantities are available in plastic tubes of 50 pieces. Figure 17: Reel Dimensions DIRECTION OF FEED Figure 18: Tape Dimensions 14 PRELIMINARY DATA SHEET - Rev 1.3 08/2001 ARA2005 NOTES PRELIMINARY DATA SHEET - Rev 1.3 08/2001 15 ARA2005 ORDERING INFORMATION OR D ER N U MB ER ARA2005S8P1 ARA2005S8P0 TEMPER ATU R E R AN GE -40 to 85 0C -40 to 85 0C PAC K AGE D ESC R IPTION 28 Pi n SSOP 28 Pi n SSOP C OMPON EN T PAC K AGIN G 3,500 pi ece tape and reel Plasti c tubes (50 pi eces per tube) 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. 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. WARNING 16 PRELIMINARY DATA SHEET - Rev 1.3 08/2001