MT1550

M I C R O T U NE RF SILICON AND SYSTEMS SOLUTIONS FOR BROADBAND COMMUNICATIONS, AUTOMOTIVE ELECTRONICS AND WIRELESS CONNECTIVITY MT1550 UPSTREAM AMPLIFIER PRODUCT BRIEF The MT1550 is a low-cost programmable-gain power amplifier IC for use in CATV upstream applications. The Microtune® MT1550 is a 3.3 volt part optimized ® for the DOCSIS 1.0, 1.1, 2.0 and MT1550 APPLICATIONS • • • Cable modems Telephony over cable Set-top box CATV The MT1550 is a 3.3V programmable gain upstream amplifier with integrated antialiasing filter. MT1550 Upstream Amplifier Euro-DOCSIS™ upstream standard. An on-chip input anti-aliasing filter is included to reduce external system costs. The device’s specified frequency range is from 5 MHz to 65 MHz, with an output P1dB > 67 dBmV through a 1:1 impedance-ratio transformer. A 3-wire digital serial bus controls the variable gain, with gain control available in 1 dB steps and a nominal 59 dB gain range. The MT1550 may be disabled via an external control pin. The transmitdisable mode not only minimizes output noise by shutting off the output stage, but also maintains its output impedance at nominal levels. Output transients are nominally less than 16 mVp-p at 61 dBmV output level during transmit enable/disable switching. Operating from a single 3.3 V supply, the amplifier typically draws 247 mA at maximum gain or minimum attenuation. Additional internal circuitry reduces the amplifier’s power consumption depending on gain setting. Transmit-disable mode reduces the typical current draw to 60 mA, while shutdown mode further reduces it to 85 µA. The MT1550 is available in a 20pin Quad Flat No-Lead (QFN) package with an exposed pad for the extended industrial temperature range of -40°C to +85°C. FEATURES • • • Integrated on-chip antialiasing filter P1dB of 67 dBmV Low power-up/down transients of 16 mVp-p typical at 61 dBmV output Ultra low third harmonic distortion Single 3.3 V supply 59 dB gain range Gain programmable in 1 dB steps Low transmit output noise floor: -50 dBmV in 160 kHz Low transmit-disable output noise: -68 dBmV Two power-down modes DOCSIS 1.0, 1.1, 2.0 and Euro-DOCSIS compatible • • • • • • • • MICROTUNE M T15 50 UPSTR EAM AMPLI FIER PRODUCT BRIEF Vcc1 Vcsns Vrsns PARAMETER Supply voltage Supply current, shutdown mode Gain code = 52 to 63 MIN 3.15 TYP 85 247 MAX 3.45 125 UNIT V µA mA Vcc2 17 SUPPLY CURRENT, TRANSMIT MODE, FILTER ENABLED DIGITAL INPUT High voltage Low voltage Current 2.0 0.7 0 V V µA 16 20 18 19 GND2 DC ELECTRICAL CHARACTERISTICS GND1 Vin+ VinDGND CS 1 2 3 4 5 15 14 13 12 11 NC Vout+ VoutNC Vcm AC ELECTRICAL CHARACTERISTICS PARAMETER Output 1dB compression point Output step size MIN TYP 70 1 -30 29 1.1 1.5 MAX UNIT dBmV dB dB dB dB dB VOLTAGE GAIN GAIN RESPONSE Fin = 42MHz Fin = 65MHz SCLK SDA TXEN SHDN VCC2 TXEN TXEN enable/disable time TXEN transient duration TXEN transient step size, VOUT = 61dBmV TXEN transient step size, min gain 5 1.5 16 64 7 1.55 16 µs µs mVp-p VCC1 MT1550 Pin Diagram mVp-p kΩ dB GND2 10 Gain code = 4 Gain code = 63 8 6 7 9 INPUT/OUTPUT Input impedance Output return loss, Z0 = 75Ω VIN+ Vcc VOUT+ 1:1 Ohms VCM RFout Anti-Alias Filter Variable Attenuator Power Amp STRESS RATINGS PARAMETER VCC (VCC1, VCC2) VOUT+, VOUTInput voltage levels (all inputs), VCM Junction temperature Storage temperature range Lead temperature (soldering, 4 seconds) -40 0.1 µF CEXT VIN- MIN -0.7 -0.7 −0.7 MAX 5 5.5 VCC + 0.7 +125 +150 +245 UNIT V V V DGND VCSNS SHDN SCLK Filter Tuning Serial Interface PA Control VOUTVRSNS RSNS 4.70 kΩ 1% 0.1 µF °C °C CSNS 59 pF 5% MT1550 Block Diagram Microtune, Inc., 2201 Tenth Street, Plano, TX 75074, USA Tel: +1-972-673-1600, Fax: +1-972-673-1602, E-mail: sales@microtune.com, Web site: www.microtune.com For a detailed list of design centers, sales offices, and sales representatives, visit our Web site at www.microtune.com. The information in this document is believed to be accurate and reliable. Microtune assumes no responsibility for any consequences arising from the use of this information, nor from any infringement of patents or the rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or other rights of Microtune. The information in this publication replaces and supersedes all information previously supplied, and is subject to change without notice. The customer is responsible for assuring that proper design and operating safeguards are observed to minimize inherent and procedural hazards. Microtune assumes no responsibility for applications assistance or customer product design. The devices described in this document are not authorized for use in medical, life-support equipment, or any other application involving a potential risk of severe property or environmental damage, personal injury, or death without prior express written approval of Microtune. Any such use is understood to be entirely at the user’s risk. Microtune is a registered trademark of Microtune, Inc. MicroTuner, MicroStreamer, VideoCaster, DataCaster, and the Microtune logo are trademarks of Microtune, Inc. All other trademarks belong to their respective companies. Microtune’s products are protected by one or more of the following U.S. patents: DE10011662; GB1026825; ES1026825; DE19628727; DE19904588.7-09; DE348698; FR348698; GB348698; IT348698; DE3821716; US5,933,946; DE50000802.7-08; DE552624 and additional patents pending or filed. Entire contents Copyright © 1996 - 2005 Microtune, Inc. 072105 PB-00058 — Rev 1.2 TXEN SDA °C CS October 2005