Download: MANUA L EVALUA T EET FOLLOW S General Description Features

19-4797; Rev 0; 2/99

MANUA L

ION KIT

EVALUA T

DATA SH

EET FOLLOW S General Description Features

The MAX2470/MAX2471 are flexible, low-cost, high- ♦ +2.7V to +5.5V Supply Range reverse-isolation buffer amplifiers for applications with discrete and module-based VCO designs. Both feature ♦ Input Frequency Range differential 50Ω outputs for driving a single differential High: 10MHz to 500MHz (MAX2470/2471) (balanced) load or two separate single-ended (unbal- Low: 10MHz to 200MHz (MAX2470) anced) 50Ω loads. The MAX2470 offers a single-ended ♦ >14dB Power Gain at 200MHz input and has two selectable frequency ranges of oper- ation: 10MHz to 500MHz and 10MHz to 200MHz. The ♦ 64dB Typical Reverse Isolation at 200MHz MAX2471 offers a differential input and operates from ♦ Low-Distortion Output Drive 10MHz to 500MHz. The MAX2470/MAX2471 also feature high input impedance for maximum flexibility, enabling ♦ Ultra-Small SOT23-6 Package them to be used with a variety of oscillator topologies. High reverse isolation combined with low supply current ♦ High Input Impedance make them ideal for applications requiring high perfor- ♦ Single-Ended (MAX2470) or Differential mance with low power. (MAX2471) Inputs These devices are also ideal for use as active baluns. The MAX2470 converts a single-ended input to a differ- ential output. The MAX2471 is useful as a differential buffer stage or to convert from a differential input to two Ordering Information single-ended outputs. PIN- SOT TOP PART TEMP. RANGE The MAX2470 operates from a single +2.7V to +5.5V PACKAGE MARK supply. At -5dBm output power, it consumes 5.5mA in MAX2470EUT-T -40°C to +85°C 6 SOT23-6 AAAX the high-frequency range and only 3.6mA in the MAX2471EUT-T -40°C to +85°C 6 SOT23-6 AAAY low-frequency range. The MAX2471 operates from a +2.7V to +5.5V single supply and consumes 5.5mA. Both devices are available in ultra-small SOT23-6 plas- Typical Operating Circuits tic packages, requiring minimal board space.

VCC Applications HI/LO

Cellular and PCS Mobile Phones ISM-Band Applications BIAS MAX2470 Active Baluns OUT General-Purpose Buffers/Amplifiers IN 50Ω

OUT Pin Configuration 50Ω GND VCC

TOP VIEW OUT16VCC BIAS MAX2471 MAX2470 GND 2 MAX2471 5 IN IN

OUT

50Ω OUT34HI/LO (IN) IN OUT 50Ω SOT23-6 GND ( ) ARE FOR MAX2471 _ Maxim Integrated Products 1

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769.

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ABSOLUTE MAXIMUM RATINGS

VCC to GND...-0.3V to +7V Operating Temperature Range ...-40°C to +85°C IN to GND...-0.3V to (VCC + 0.3V) or 3.7V (whichever is lower) Junction Temperature ...+150°C IN to IN ...-2.2V to +2.2V Storage Temperature Range ...-65°C to +150°C HI/LO to GND ...-0.3V to (VCC + 0.3V) Lead Temperature (soldering, 10sec ) ...+300°C Continuous Power Dissipation SOT23-6 (derate 8.7mW/°C above +70°C)...696mW Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

DC ELECTRICAL CHARACTERISTICS

(Typical Operating Circuit, VCC = +2.7V to +5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +3V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage Range VCC 2.7 5.5 V No signal 5.1 7.4 HI/LO = VCC POUT = -5dBm, 5.5 RLOAD = 100Ω diff. Supply Current ICC mA No signal No signal 3.0 4.5 HI/LO = GND POUT = -5dBm, 3.6 RLOAD = 100Ω diff. HI/LO Input Level High VIH 2.0 V HI/LO Input Level Low VIL 0.6 V HI/LO Input Bias Current IIN VHI/LO = GND or VCC -10 10 µA

AC ELECTRICAL CHARACTERISTICS—MAX2470

(VCC = +3V, HI/LO = VCC, all outputs are differentially measured between OUT and OUT driving a 50Ω load through a 180° hybrid, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Frequency Range HI/LO = VCC 10 500 f MHz (Note 2) IN HI/LO = GND 10 200 fIN = 10MHz 14.9 fIN = 200MHz 14.9 HI/LO = VCC fIN = 500MHz, 8.9 13.3 15.3 TA = TMIN to TMAX Gain (Note 3) IS21I2 dB fIN = 10MHz 13.8 fIN = 200MHz 14.1 HI/LO = GND fIN = 200MHz, 9.9 13.4 15.0 TA = TMIN to TMAX Voltage Gain (Note 4) AV fIN = 10MHz, HI/LO = GND 16 V/V fOUT = 500MHz, 10.2 HI/LO = VCC Noise Figure NF RSOURCE = 50Ω dB fOUT = 200MHz, fOUT = 200MHz, 10.2 RHI/LO = GND RHI/LO = GND 2 _,

AC ELECTRICAL CHARACTERISTICS—MAX2470 (continued)

(VCC = +3V, HI/LO = VCC, all outputs are differentially measured between OUT and OUT driving a 50Ω load through a 180° hybrid, TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Maximum Output VSWR 10MHz < fOUT < 500MHz, HI/LO = VCC 1.5:1

VSWR

(OUT, OUT) (Note 5) OUT 10MHz < fOUT < 200MHz, HI/LO = GND 1.2:1 fIN = 100MHz 75 HI/LO = VCC Reverse Isolation fIN = 500MHz 48 IS I2 dB (Note 6) 12 fIN = 100MHz 75 HI/LO = GND fIN = 200MHz 64 Isolation OUT to OUT fIN = 500MHz, HI/LO = VCC 37 dB (Note 7) fIN = 200MHz, HI/LO = GND 45 fIN = 500MHz, POUT = -5dBm, HI/LO = VCC -26 Harmonic Suppression dBc fIN = 200MHz, POUT = -5dBm, HI/LO = GND -30

AC ELECTRICAL CHARACTERISTICS—MAX2471

(Typical values are measured at VCC = +3V, TA = +25°C, unless otherwise noted.) (Note 8) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Frequency Range fIN 10 500 MHz(Note 2) fIN = 10MHz 15.9 Gain (Note 3) IS21I2 fIN = 200MHz 16.9 dB fIN = 500MHz, TA = TMIN to TMAX 11.3 15.6 17.8 Voltage Gain (Note 4) AV fIN = 10MHz 16 V/V Noise Figure NF fOUT = 500MHz, RSOURCE = 50Ω 8.4 dB Maximum Output VSWR VSWR 10MHz < f < 500MHz 1.5:1 (OUT, OUT) (Note 5) OUT OUT fIN = 100MHz 74 Reverse Isolation IS12I2 dB fIN = 500MHz 57 Isolation OUT to OUT (Note 7) fIN = 500MHz 35 dB Harmonic Suppression fIN = 500MHz, POUT = -5dBm -29 dBc Note 1: Limits are 100% production tested at TA = +25°C. Limits over the entire operating temperature range are guaranteed by design and characterization but are not production tested. Note 2: The part has been characterized over the specified frequency range. Operation outside of this range is possible but not guaranteed. Note 3: Gain specified for POUT = -5dBm. Note 4: Voltage gain measured with no input termination and no output load. Note 5: Output VSWR is a single-ended measurement for each OUT and OUT. Note 6: OUT to IN isolation with OUT terminated with 50Ω. Note 7: Input terminated with 50Ω. Note 8: Unless otherwise noted: all inputs are differentially measured between IN and IN driven by a 50Ω load through a 180° hybrid; all outputs are differentially measured between OUT and OUT driving a 50Ω load through a 180° hybrid. _ 3,

Typical Operating Characteristics

(VCC = +3.0V, MAX2470 output and MAX2471 input and output measurements taken differentially, TA = +25°C, unless otherwise noted.) MAX2470 SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX2470 (HI/LO = VCC) AND MAX2471 MAX2470 (HI/LO = GND) SUPPLY CURRENT vs. SUPPLY VOLTAGE OUTPUT POWER vs. INPUT POWER 4.0 6.0 0 -5dBm OUTPUT POWER -5dBm OUTPUT POWER5.9 -1 3.9 fIN = 200MHz fIN = 500MHz -2 HI/LO = GND 5.8 HI/LO = GND (MAX2470) -3 3.8 5.7 -4 -5 HI/LO = GND5.6 3.7 fIN = 200MHzTA = +25°C -6 5.5 TA = +25°C -7 3.6 TA = +85°C 5.4 T = +85°C -8 HI/LO = VA CCf = 500MHz 5.3 -9 IN 3.5 -10 5.2 -11 3.4 5.1 -12 TA = -40°C 5.0 TA = -40°C -13 3.3 -14 4.9 -15 3.2 4.8 -16 2.5 3.0 3.5 4.0 4.5 5.0 5.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 -30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) INPUT POWER (dBm) MAX2470 MAX2470 MAX2470 TRANSDUCER GAIN vs. FREQUENCY TRANSDUCER GAIN vs. FREQUENCY NOISE FIGURE vs. FREQUENCY (HI/LO = GND) (HI/LO = VCC) (HI/LO = GND) 16.0 17.0 12.0TA = -40°C TA = -40°C 15.0 16.0 HI/LO = GND 11.5 14.0 15.0 TA = +25°C TA = +25°C 13.0 14.0 T 11.0A = +85°C 12.0 13.0 TA = +85°C 11.0 12.0 10.5 10.0 11.0 10.0 9.0 HI/LO = GND 10.0 HI/LO = VCC 8.0 9.0 9.5 0 50 100 150 200 0 100 200 300 400 500 0 50 100 150 200 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) MAX2470 NOISE FIGURE vs. FREQUENCY MAX2470 MAX2470 (HI/LO = VCC) REAL INPUT IMPEDANCE vs. FREQUENCY IMAGINARY INPUT IMPEDANCE vs. FREQUENCY 12.0 10,000 0 HI/LO = V HI/LO = VCCCC HI/LO = VCC -500 11.5 1000 -1000 11.0 -1500 -2000 10.5 10 -2500 10.0 1 -3000 0 100 200 300 400 500 0 50 100 150 200 250 300 350 400 450 500 0 100 200 300 400 500 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) 4 _ NOISE FIGURE (dB) IS21I2 (dB) SUPPLY CURRENT (mA) MAX2470/71-07 MAX2470/71-04 MAX2470/71-01 RE [ZIN] (Ω) IS21I2 (dB) SUPPLY CURRENT (mA) MAX2470/71-08 MAX2470/71-05 MAX2470/71-02 IM [ZIN] (Ω) NOISE FIGURE (dB) OUTPUT POWER (dBm) MAX2470/71-09 MAX2470/71-06 MAX2470/71-03,

Typical Operating Characteristics (continued)

(VCC = +3.0V, MAX2470 output and MAX2471 input and output measurements taken differentially, TA = +25°C unless otherwise noted.) MAX2470 MAX2470 MAX2471 OUTPUT VSWR vs. FREQUENCY OUTPUT ISOLATION vs. FREQUENCY OUTPUT POWER vs. INPUT POWER 1.50 90 2 HI/LO = VCC HI/LO = VCC INPUT TERMINATED IN 50Ω 80 SINGLE-ENDED 0 SINGLE-ENDED MEASUREMENT MEASUREMENT 70 OUT TO IN -2 fIN = 200MHz -4 fIN = 500MHz OUT 60 OUT TO IN 1.25 -6 OUT -8 -10 OUT TO OUT 30 INPUT TERMINATED IN 50Ω -12 1.00 20 -14 0 100 200 300 400 500 0 100 200 300 400 500 -30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 FREQUENCY (MHz) FREQUENCY (MHz) INPUT POWER (dBm) MAX2471 DIFFERENTIAL TRANSDUCER MAX2471 MAX2471 POWER GAIN vs. FREQUENCY NOISE FIGURE vs. FREQUENCY REAL INPUT IMPEDANCE vs. FREQUENCY 17.5 8.50 10,000TA = +25°C 17.0 8.25 16.5 1000 TA = +85°C16.0 8.00 TA = -40°C 15.5 100 7.75 15.0 7.50 10 14.5 14.0 7.251050 100 150 200 250 300 350 400 450 500 0 50 100 150 200 250 300 350 400 450 500 0 50 100 150 200 250 300 350 400 450 500 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) MAX2471 IMAGINARY INPUT IMPEDANCE MAX2471 MAX2471 vs. FREQUENCY OUTPUT VSWR vs. FREQUENCY OUTPUT ISOLATION vs. FREQUENCY 500 1.50 90 INPUT TERMINATED SINGLE-ENDED SINGLE-ENDED MEASUREMENT 80 MEASUREMENT 0 VSWR OUT 70 OUT TO IN 1.25 VSWR OUT -500 OUT TO OUT INPUT TERMINATED IN 50Ω -1000 1.00 20 0 100 200 300 400 500 0 100 200 300 400 500 0 100 200 300 400 500 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) _ 5 IM [ZIN] (Ω) TRANSDUCER POWER GAIN (dB) OUTPUT VSWR MAX2470/71-16 MAX2470/71-13 MAX2470/71-10 OUTPUT VSWR NOISE FIGURE (dB) OUTPUT ISOLATION (dB) MAX2470/71-17 MAX2470/71-14 MAX2470/71-11 OUTPUT ISOLATION (dB) RE [ZIN] (Ω) OUTPUT POWER (dBm) MAX2470/71-18 MAX2470/71-15 MAX2470/71-12,

Pin Description PIN

NAME FUNCTION MAX2470 MAX2471 Differential Noninverting Buffer Output. Broadband 50Ω output. AC coupling is required. 1 1 OUT Do not DC couple to this pin. RF Ground. Connect to the ground plane as close as possible to the IC to minimize22GND ground path inductance. Differential Inverting Buffer Output. Broadband 50Ω output. AC coupling is required. Do33OUT not DC couple to this pin. Bias and Bandwidth Control Input. Connect to VCC to set internal bias for higher band- 4 — HI/LO width operation (10MHz to 500MHz). Connect to GND to set internal bias for lower band- width operation (10MHz to 200MHz) and to reduce overall current consumption. Differential Inverting Buffer Input. High impedance input to buffer amplifier. See Setting — 4 IN The Input Impedance section. Differential Noninverting Buffer Input. High impedance to buffer amplifier. See Setting The55IN Input Impedance section. 6 6 VCC Supply Voltage Input. +2.7V < VCC < +5.5V. _ Detailed Description Output Considerations The MAX2470 and MAX2471 incorporate fully differen- Bandwidth Control Circuitry tial output stages capable of driving an AC-coupled The MAX2470 features a logic-controlled bias circuit 100Ω differential load or two AC-coupled 50Ω single- which optimizes the performance for input frequencies ended loads. This is ideal for applications that require from 10MHz to 500MHz (HI/LO = VCC) and 10MHz to the oscillator to drive two application circuits (e.g. mixer 200MHz (HI/LO = GND). Operating with HI/LO = GND and PLL) simultaneously. The high output-to-output iso- significantly reduces power consumption. lation ensures minimal interaction between multiple _ Applications Information load circuits. Input Considerations Layout and Power-Supply BypassingA properly designed PC board is essential to any RF/ The MAX2470/MAX2471 offer high-impedance inputs, microwave circuit. Be sure to use controlled impedance ideal for low-distortion buffering of a VCO. For applica- lines on all high-frequency inputs and outputs. Bypass tions with discrete transistor-based oscillator designs, the power supply with decoupling capacitors as close to simply AC-couple the oscillator directly to the inputs. the V pins as possible. For long V lines (inductive), it The buffer’s high input impedance results in minimal CC CCmay be necessary to add additional decoupling capaci- loading on the oscillator. For still higher real input tors located further away from the device package. impedance and reduced loading effects, match the inputs with a shunt-L matching circuit followed by a Proper grounding of GND is essential. If the PC board series blocking capacitor. For use with 50Ω VCO mod- uses a topside RF ground, connect GND directly to it. ules, terminate the buffer input(s) with a 50Ω shunt For a board where the ground plane is not on the com- resistor followed by a series-blocking capacitor. This ponent side, the best technique is to connect GND to provides a very stable 50Ω termination and increases the board with a plated through-hole (via) to the ground reverse isolation. For those applications needing both plane close to the package. high gain and good input match, reactively match the buffer inputs to 50Ω with simple two-element matching circuits followed by a series blocking capacitor. 6 _, Chip Information TRANSISTOR COUNT: 67 Package Information_76LSOT.EPS,

NOTES

8 _]

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