ARA2001 Reverse Amplifier with Step Attenuator Data Sheet - Rev 2.2 FEATURES * * * * * * * Low cost integrated amplifier with step attenuator Attenuation Range: 0-58 dB, adjustable in 1dB increments via a 3 wire serial control Meets DOCSIS distortion requirements at +60dBmV output signal level Low distortion and low noise Frequency range: 5-100MHz 5 Volt operation -40 to +85 0C temperature range APPLICATIONS * * * * * MCNS/DOCSIS Compliant Cable Modems CATV Interactive Set-Top Box Telephony over Cable Systems OpenCable Set-Top Box Residential Gateway S23 Package 28 Pin SSOP with Exposed Paddle PRODUCT DESCRIPTION The ARA2001 is 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 uses a balanced circuit design that exceeds the MCNS/DOCSIS requirement for harmonic performance at a +60dBmV output level while only requiring a single polarity +5V supply. Both the input and output are matched to 75 ohms with an appropriate transformer. The precision attenuator provides up to 58 dB of attenuation in 1 dB increments. The ARA2001 is offered in a 28-pin SSOP package featuring an exposed paddle on the bottom of the package. Clock Data Enable Balun Low Pass Filter ARA2001 Upstream QPSK/16QAM Modulator RAM Clock Data Transmit Enable/Disable 5-42 MHz Microcontroller with Ethernet MAC MAC Clock ROM Data 44 MHz Diplexer 54-860 MHz DoubleConversion Tuner SAW Filter QAM Receiver with FEC 10Base-T Transceiver Figure 1. Cable Modem or Set Top Box Application Diagram 07-2001 RJ45 Connector ARA2001 GaAs IC ATTOUT (+) ATTIN (+) A1OUT (+) A2IN (+) A1IN (+) 32 dB ISET1 16 dB 8 dB 4 dB 2 dB A2OUT (+) 1 dB ISET2 EFET EFET Vg1 Vg2 A1IN (-) A2OUT (-) A1OUT (-) A2IN (-) ATTIN (-) ATTOUT (-) 32 dB 16 dB 8 dB 4 dB 2 dB 1 dB P5 P4 P3 P2 P1 P0 Buffer Clock Data 8 8-Bit Shift Register/ Address Control Latch Enable CMOS IC (Serial to Parallel Interface) Figure 2: Functional Block Diagram 1 GND GND 28 2 VATTN N/C 27 3 ATTIN (+) ATTOUT (+) 26 4 A1OUT (+) A2IN (+) 25 5 A1IN (+) A2OUT (+) 24 6 Vg1 Vg2 23 7 ISET1 ISET2 22 8 A1IN (-) A2OUT (-) 21 9 A1OUT (-) A2IN (-) 20 10 ATTIN (-) ATTOUT (-) 19 11 VCMOS GNDCMOS 18 12 CLK N/C 17 13 DAT N/C 16 14 EN N/C 15 Figure 3: Pin Out 2 Data Sheet - Rev 2.2 07-2001 ARA2001 Table 1: Pin Description PIN N AME 1 GND 2 D ESC R IPTION PIN N AME Ground 15 N/C No C onnecti on (1) VATTN Supply for Attenuator 16 N/C No C onnecti on (1) 3 ATTIN (+) Attenuator (+) Input (2) 17 N/C No C onnecti on (1) 4 A1OUT (+) Ampli fi er A1 (+) Output 18 GND CMOS Ground for D i gi tal C MOS C i rcui t 5 A1IN (+) Ampli fi er A1 (+) Input (2) 19 ATTOUT (-) Attenuator (-) Output (2) 6 V g1 Ampli fi er A1 (+/-) C ontrol 20 A2IN (-) Ampli fi er A2 (-) Input (2) 7 ISET1 Ampli fi er A1 (+/-) C urrent Adjust 21 A2OUT (-) Ampli fi er A2 (-) Output 8 A1IN (-) Ampli fi er A1 (-) Input (2) 22 ISET2 Ampli fi er A2 (+/-) C urrent Adjust 9 A1OUT (-) Ampli fi er A1 (-) Output 23 V g2 Ampli fi er A2 (+/-) C ontrol 10 ATTIN (-) Attenuator (-) Input (2) 24 11 VCMOS Supply For D i gi tal C MOS C i rcui t 25 A2 IN (+) Ampli fi er A2 (+) Input (2) 12 C LK C lock 26 ATTOUT (+) Attenuator (+) Output (2) 13 D AT D ata 27 N/C No C onnecti on (1) 14 EN Enable 28 GND Ground A2 OUT (+) D ESC R IPTION Ampli fi er A2 (+) Output Notes: (1) All N/C pins should be grounded. (2) Pins should be AC-coupled. No external DC bias should be applied. Data Sheet - Rev 2 07-2001 3 ARA2001 ELECTRICAL CHARACTERISTICS Table 2: Absolute Minimum and Maximum Ratings PAR AMETER MIN MAX U N IT Analog Supply (pi ns 2, 4, 9, 21, 24) 0 9 VD C D i gi tal Supply: VCMOS (pi n 11) 0 6 VD C Ampli fi er C ontrols Vg1, Vg2 (pi ns 6, 23) -5 2 V RF Power at Inputs (pi ns 5, 8) - +60 dBmV D i gi tal Interface (pi ns 12, 13, 14) -0.5 VCMOS+0.5 V Storage Temperature -55 +200 0 C Solderi ng Temperature - 260 0 C Solderi ng Ti me - 5 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, 5, 8, 10, 19, 20, 25 and 26 should be AC-coupled. No external DC bias should be applied. 2. Pins 7 and 22 should be grounded or pulled to ground through a resistor. No external DC bias should be applied. Table 3: Operating Ranges PAR AMETER MIN TYP MAX U N IT Ampli fi er Supply: VDD (pi ns 4, 9, 21, 24) 4.5 5 7 VD C VDD-0.5 5 7 VD C 3.0 - 5.5 VD C D i gi tal Interface (pi ns 12, 13, 14) 0 - VCMOS V Ampli fi er C ontrols Vg1, Vg2 (pi ns 6, 23) -5 1 2 V C ase Temperature -40 25 85 Attenuator Supply: VATTN (pi n 2) D i gi tal Supply: VCMOS (pi n 11) 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 Data Sheet - Rev 2.2 07-2001 ARA2001 Table 4: DC Electrical Specifications TA=25C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER MIN TYP MAX U N IT C OMMEN TS Ampli fi er A1 C urrent (pi ns 4, 9) - 48 2.4 80 6 mA Tx enabled Tx di sabled Ampli fi er A2 C urrent (pi ns 21, 24) - 77 3.7 120 9 mA Tx enabled Tx di sabled Attenuator C urrent (pi n 2) - 9 15 mA Total Power C onsumpti on - 0.67 75 1.08 150 W mW Tx enabled Tx di sabled Table 5: AC Electrical Specifications TA=25C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER MIN TYP MAX U N IT Gai n (10 MHz) 27.5 29.3 30.5 dB 0 dB attenuati on setti ng Gai n Flatness - 0.75 1.5 - dB 5 to 42 MHz 5 to 65 MHz Gai n Vari ati on over Temperature - -0.006 - dB/C 0.65 1.6 3.6 7.5 15.0 30.2 0.83 1.70 3.75 7.75 15.40 30.75 1.00 2.05 4.0 8.0 15.8 31.3 dB 58.6 60.3 - dB 2nd Harmoni c D i storti on Level (10 MHz) - -75 -53 dB c +60 dBmV i nto 75 Ohms 3rd Harmoni c D i storti on Level (10 MHz) - -60 -53 dB c +60 dBmV i nto 75 Ohms 78 - - dBmV 1 dB Gai n C ompressi on Poi nt - 68.5 - dBmV Noi se Fi gure - 3.0 4.0 dB Attenuati on Steps 1 dB 2 dB 4 dB 8 dB 16 dB 32 dB Maxi mum Attenuati on 3rd Order Output Intercept C OMMEN TS Monotoni c Includes i nput balun loss Note: As measured in ANADIGICS test fixture Data Sheet - Rev 2 07-2001 5 ARA2001 continued: AC Electrical Specifications TA=25C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (Tx enabled); Vg1, Vg2 = 0 V (Tx disabled) PAR AMETER MIN TYP MAX U N IT C OMMEN TS Output Noi se Power Acti ve / No Si gnal / Mi n. Atten. Set. Acti ve / No Si gnal / Max. Atten. Set. - - -38.5 -53.8 dBmV Any 160 kHz bandwi dth from 5 to 42 MHz Isolati on (45 MHz) i n Tx di sable mode - 65 - dB D i fference i n output si gnal between Tx enable and Tx di sable D i fferenti al Input Impedance - 300 - Ohms between pi ns 5 and 8 (Tx enabled) Input Impedance - 75 - Ohms wi th transformer (Tx enabled) Input Return Loss (75 Ohm characteri sti c i mpedance) - -20 -5 -12 - dB D i fferenti al Output Impedance - 300 - Ohms between pi ns 21 and 24 Output Impedance - 75 - Ohms wi th transformer Output Return Loss (75 Ohm characteri sti c i mpedance) - -17 -15 -12 -10 dB Output Voltage Transi ent Tx enable / Tx di sable - 4 100 7 mVp-p Note: As measured in ANADIGICS test fixture 6 Data Sheet - Rev 2.2 07-2001 Tx enabled Tx di sabled Tx enabled Tx di sabled 0 dB attenuator setti ng 24 dB attenuator setti ng Control A1 0 / +3 V Control A2 0 / +3 V +5 V +5 V 1uF 2K Ohms 2K Ohms 1uF 1K Ohms 0.1uF 2K Ohms Turns Ratio 1:2 470pF 1000pF 1000pF 1.2K Ohms 3.9 Ohms 1000pF 1000pF 10uH 1uF 1uF +5 V 0.1uF GND 2 VATTN +5 V GND 0.1uF N/C 27 3 ATTIN (+) ATTOUT (+) 26 4 A1OUT (+) A2IN (+) 25 A2OUT (+) 24 5 A1IN (+) 6 Vg1 7 ISET1 8 A1IN (-) 9 A1OUT (-) 10 ATTIN (-) 11 VCMOS 1K Ohms 28 2K Ohms 470pF 470pF Turns Ratio 2:1 1500pF RF Output (75 Ohms) 23 Vg2 ISET2 22 A2OUT (-) 21 A2IN (-) 20 ATTOUT (-) 19 GNDCMOS 18 N/C 17 12 CLK 13 DAT N/C 16 14 EN N/C Toko Balun 616PT-1030 470pF 15 ARA2001 Data 0.1uF Enable 1.2K Ohms Clock Figure 4: Test Circuit Data Sheet - Rev 2 07-2001 RF Input (75 Ohms) 1 10uH Note: Tx Enable: Control A1 and Control A2 = +3V Tx Disable: Control A1 and Control A2 = 0V ARA2001 7 ARA2001 PERFORMANCE DATA Attenuation (dB) Figure 5: Attenuation Level vs Control Word 64 60 56 52 48 44 40 36 32 28 24 20 16 12 8 4 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Control Word Figure 6: Gain & Noise Figure vs Frequency Noise Figure 8 30 7 25 6 20 5 15 4 10 3 5 NF (dB) Gain (dB) Gain 35 2 10 30 50 70 90 Frequency (MHz) Figure 7: Gain & Noise Figure vs VDD GAIN (dB) Noise Figure 6 32 5 29 4 26 3 23 2 Measured @ 30 MHz 20 1 3 4 5 VDD ( Volts ) 8 Data Sheet - Rev 2.2 07-2001 6 7 NF (dB) Gain 35 ARA2001 Figure 8: Gain & Noise Figure vs Temperature GAIN (dB) Noise Figure 6 32 5 29 4 26 3 23 2 NF (dB) Gain 35 Measured @ 30 MHz 20 1 -40 -25 -10 5 20 35 50 65 80 o Temperature (C ) Figure 9: Harmonic Distortion vs VDD POUT = 58dBmV 2nd Harmonic 3rd Harmonic -20 Harmonic Level (dBc) -30 -40 -50 -60 -70 Measured @ 5 MHz -80 3 4 5 6 7 VDD ( Volts ) Figure 10: Harmonic Distortion vs VDD POUT = 58dBmV 2nd Harmonic 3rd Harmonic -20 Harmonic Level (dBc) -30 -40 -50 -60 -70 Measured @ 12 MHz -80 3 4 5 6 7 VDD ( Volts ) Data Sheet - Rev 2 07-2001 9 ARA2001 Figure 11: Harmonic Distortion vs Temperature POUT = 58dBmV 2nd Harmonic 3rd Harmonic -40 Harmonic level (dBc) -45 -50 -55 -60 -65 -70 -75 Measured @ 5 MHz -80 -40 -25 -10 5 20 35 50 65 80 Temperature (Co) Figure 12: Harmonic Distortion vs Power Out 2nd 3rd -30 -35 Harmonics (dBc) -40 -45 -50 -55 -60 -65 -70 -75 49 51 53 55 57 59 61 63 65 67 Pout (dBmV) Figure 13: Transients vs Attenuation POUT = 55dBmV at 0dB attenuation DOCSIS 1.1 Spec. ARA2001 ARA2001 100 90 Transient (mV) 80 70 60 50 40 30 20 10 0 0 10 20 30 40 Power Attenuation (dB) 10 Data Sheet - Rev 2.2 07-2001 50 60 ARA2001 Figure 14: Harmonic Performance over Frequency POUT = +62dBmV 2nd Harmonic 3rd Harmonic -50 Harmonic Level (dBc) -52 -54 -56 -58 -60 -62 -64 -66 -68 -70 -72 0 5 10 15 20 Frequency (MHz) 25 30 35 40 Figure 15: IIP2 & IIP3 vs Frequency IIP3 14 36 12 32 10 28 8 24 IIP3 (dBm) IIP2 (dBm) IIP2 40 6 Measured @ V DD = 5 Volts Pin = -20 dBm per tone 20 4 5 15 25 35 45 55 65 Frequency (MHz) 75 85 95 Figure 16: IIP2 & IIP3 vs VDD IIP3 15 36 11 32 7 28 3 24 IIP3 (dBm) IIP2 (dBm) IIP2 40 -1 Measured @ 65 MHz Two tones @ 29.5 MHz 20 -5 3 4 5 VDD (Volts) Data Sheet - Rev 2 07-2001 6 7 11 ARA2001 LOGIC PROGRAMMING Programming Instructions The programming word is set through an 8 bit shift register via the data, clock and enable lines. The data is entered in order with the most significant bit (MSB) first and the least significant bit (LSB) last. The enable line must be low for the duration of the data entry, then set high to latch the shift register. The rising edge of the clock pulse shifts each data value into the register. Table 6: Programming Word D ATA B IT D7 D6 D5 D4 D3 D2 D1 D0 Value P7 P6 P5 P4 P3 P2 P1 P0 Table 7: Data Description DATA D7: MSB V AL U E FU N C TION (1 = on, 0 = by pass) P7 N/A P6 N/A P5 32 dB Attenuator Bi t P4 16 dB Attenuator Bi t P3 8 dB Attenuator Bi t P2 4 dB Attenuator Bi t P1 2 dB Attenuator Bi t P0 1 dB Attenuator Bi t D6 D4 D3 CLOCK ENABLE OR ENABLE Figure 17: Serial Data Input Timing 12 Data Sheet - Rev 2.2 07-2001 D1 D0: LSB ARA2001 APPLICATION INFORMATION Transmit Enable / Disable The ARA2001 includes two amplification stages that each can be shut down through external control pins Vg1 and Vg2 (pins 6 and 23, 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 (7 and 22) 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. Thermal Layout Considerations The device package for the ARA2001 features an exposed paddle on the bottom of the package body. Use of the paddle is an integral part of the device design. Soldering this paddle 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.) A PC board layout that optimizes the benefits of the paddle is shown in Figure 18. 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 a sufficient heat sink. The recommended solder mask outline is shown in Figure 19. Figure 18: PC Board Layout Data Sheet - Rev 2 07-2001 13 ARA2001 Output Transformer Matching the output of the ARA2001 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. Proper precautions and handling are strongly recommended. Refer to the ANADIGICS application note on ESD precautions. Figure 19: Solder Mask Outline 14 Data Sheet - Rev 2.2 07-2001 ARA2001 PACKAGE OUTLINE SYMBOLS A A1 A2 b C D E H e L y T S DIMENSIONS IN INCHES MIN 0.057 0.000 0.057 0.008 0.007 0.386 0.150 0.228 0.025 0.016 --- 0 --- --- DIMENSIONS IN MILLIMETERS MAX 0.061 0.004 MIN 1.45 0.00 0.012 0.010 0.394 0.157 0.244 0.20 0.18 9.80 3.81 5.80 0.050 0.004 8 0.190 0.096 0.40 --- 0 --- --- 1.45 .64 MAX 1.55 0.10 NOTE 1. PACKAGE BODY SIZES EXCLUDE MOLD FLASH AND GATE BURRS 2. TOLERANCE 0.004in.[0.10 mm] UNLESS OTHERWISE SPECIFIED 3. CONTROLLING DIMENSION ARE INCHES. 4. REF. - MO-137 0.30 0.25 10.00 4.00 6.20 1.27 0.10 8 4.82 2.43 Figure 20: S23 Package Outline - 28 Pin SSOP with Exposed Paddle Data Sheet - Rev 2 07-2001 15 ARA2001 COMPONENT PACKAGING Volume quantities of the ARA2001 are supplied on tape and reel. Each reel holds 3,500 pieces. Smaller quantities are available in plastic tubes of 50 pieces. Figure 21: Reel Dimensions DIRECTION OF FEED Figure 22: Tape Dimensions 16 Data Sheet - Rev 2.2 07-2001 ARA2001 NOTES Data Sheet - Rev 2 07-2001 17 ARA2001 NOTES 18 Data Sheet - Rev 2.2 07-2001 ARA2001 NOTES Data Sheet - Rev 2 07-2001 19 ARA2001 ORDERING INFORMATION OR D ER N U MB ER TEMPER ATU R E R AN GE PAC K AGE D ESC R IPTION ARA2001S23TR -40 to 85 0C 28 Pi n SSOP wi th Exposed Paddle 3,500 pi ece tape and reel ARA2001S23P0 -40 to 85 0C 28 Pi n SSOP wi th Exposed Paddle Plasti c tubes (50 pi eces per tube) C OMPON EN T PAC K AGIN G 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 products 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. 20 Data Sheet - Rev 2.2 07-2001