AD8370AREZ Analog Devices Inc, AD8370AREZ Datasheet
AD8370AREZ
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AD8370AREZ Summary of contents
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FEATURES Programmable low and high gain (<2 dB resolution) Low range: − +17 dB High range Differential input and output 200 Ω differential input 100 Ω differential output 7 dB noise figure @ ...
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AD8370 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ...
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SPECIFICATIONS 25° 200 Ω 100 Ω at gain code HG127, 70 MHz p-p differential output, unless otherwise noted Table 1. Parameter DYNAMIC PERFORMANCE −3 dB ...
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AD8370 Parameter 140 MHz Gain Flatness Noise Figure 1 Second Harmonic Third Harmonic 1 Output IP3 Output 1 dB Compression Point 190 MHz Gain Flatness Noise Figure 1 Second Harmonic 1 Third Harmonic Output IP3 Output 1 dB Compression Point ...
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ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage PWUP, DATA, CLCK, LTCH Differential Input Voltage, V – V INHI INLO Common-Mode Input Voltage with Respect to INHI INLO, ICOM or OCOM Internal Power Dissipation θ ...
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AD8370 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 3. Pin Function Descriptions Pin No. Mnemonic Description 1 INHI Balanced Differential Input. Internally biased. 2, 15, PADDLE ICOM Input Common. Connect to a low impedance ground. This node is also connected to ...
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TYPICAL PERFORMANCE CHARACTERISTICS 200 Ω 100 Ω 25°C, unless otherwise noted CODE = LAST 7 BITS OF GAIN CODE (NO MSB) 60 HIGH GAIN MODE 50 ...
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AD8370 20 LOW GAIN MODE 16 HIGH GAIN MODE LOW GAIN MODE 12 HIGH GAIN MODE 8 4 UNIT CONVERSION NOTE: 0 FOR 100Ω LOAD: dBV rms = dBm–10dB FOR 1kΩ LOAD: dBV rms = dBm –4 SHADING INDICATES ±3σ ...
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FREQUENCY (MHz) Figure 16. Output Third-Order Intercept vs. Frequency at Maximum Gain kΩ ...
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AD8370 0 –10 = 100 Ω –20 –30 –40 –50 –60 – Ω –80 – 100 150 200 250 FREQUENCY (MHz) Figure 22. Harmonic Distortion vs. Frequency at ...
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LG32, LG127 60 HG32, HG127 100 FREQUENCY (MHz) Figure 28. Common-Mode Rejection Ratio vs. Frequency LG127 6 4 HG18 2 HG127 0 10 110 210 310 410 FREQUENCY ...
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AD8370 LOW GAIN 65 HIGH GAIN GAIN CODE Figure 34. Supply Current vs. Gain Code DATA FROM 136 PARTS FROM ONE BATCH LOT 20 ...
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THEORY OF OPERATION The AD8370 is a low cost, digitally controlled, fine adjustment variable gain amplifier (VGA) that provides both high IP3 and low noise figure. The AD8370 is fabricated on an ADI proprietary high performance 25 GHz silicon bipolar ...
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AD8370 OUTPUT AMPLIFIER The output impedance is approximately 100 Ω differential and, like the input preamplifier, this impedance is formed using active circuit elements. See Figure 40 for a simplified schematic of the output interface. 740Ω VCC/2 Figure 40. OPHI/OPLO ...
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APPLICATIONS BASIC CONNECTIONS Figure 44 shows the minimum connections required for basic operation of the AD8370. Supply voltages between 3.0 V and 5.5 V are allowed. The supply to the VCCO and VCCI pins should be decoupled with at least ...
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AD8370 CHOOSING BETWEEN GAIN RANGES There is some overlap between the two gain ranges; users can choose which one is most appropriate for their needs. When deciding which preamp to use, consider resolution, noise, linearity, and spurious-free dynamic range (SFDR). ...
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The AD8370 contains both digital and analog sections. Care should be taken to ensure that the digital and analog sections are adequately isolated on the PC board. The use of separate ground planes for each section connected at only one ...
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AD8370 If the amplifier is driven in single-ended mode, the input impedance varies depending on the value of the resistor used to terminate the other input as Rin = Rin + R SE DIFF TERM where R is the termination ...
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AD8370 WITH AD8138 SINGLE 4 +5V SUPPLY 2 0 –2 –4 –6 –8 – 100 1k 10k 100k 1M FREQUENCY (Hz) Figure 53. Normalized Frequency Response of the Two Solutions in Figure 51 and Figure ...
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AD8370 SOURCE SINGLE-ENDED V S EQUIVALENT BALANCED V S CONFIGURATION Figure 55. Single-Ended-to-Differential Network Conversion As an example, a second-order, Butterworth, low-pass filter design ...
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SERIAL CONTROL INTERFACE FROM 75Ω Tx-LINE C AC 100nF R 120Ω AD8370 1nF 100nF 0.1μF 0.1μ Figure 58. ADC Interface Example ...
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AD8370 EVALUATION BOARD AND SOFTWARE The evaluation board allows quick testing of the AD8370 by using standard 50 Ω test equipment. The schematic is shown in Figure 59. Transformers T1 and T2 are used to transform 50 Ω source and ...
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Table 7. AD8370 Evaluation Board Configuration Options Component Function VS, GND, VOCM Power Interface Vector Pins. Apply supply voltage between VS and GND. The VOCM pin allows external monitoring of the common-mode input and output bias levels. SW1, R8, Device ...
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AD8370 Figure 61. Evaluation Board Top Silkscreen Figure 62. Evaluation Board Bottom Silkscreen Figure 63. Evaluation Board Top Figure 64. Evaluation Board Bottom Rev Page ...
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APPENDIX CHARACTERIZATION EQUIPMENT An Agilent N4441A Balanced-Measurement System was used to obtain the gain, phase, group delay, reverse isolation, CMRR, and s-parameter information contained in this data sheet. With the exception of the s-parameter information, T-attenuator pads were used to ...
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AD8370 –22.5dB SERIAL DATA SOURCE V 5.0V S 1nF T1 MINI CIRCUITS TC4-1W 0Ω AD8370 1nF V 5.0V S 1μF 1nF 1μF 1nF 1nF ...
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AGILENT 8648D SERIAL DATA SIGNAL SOURCE GENERATOR RF OUT 1nF T1 MINI CIRCUITS TC4-1W 0Ω AD8370 1nF V 5.0V S 1μF 1nF 1nF Figure 68. Gain Step Time Domain Response ...
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... C to +85 ° C AD8370ARE –40 ° +85 ° C AD8370ARE-REEL7 –40 ° +85 ° AD8370AREZ –40 ° +85 ° AD8370AREZ-RL7 AD8370-EVAL Pb-free part. © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03692–0–7/05(A) 5.10 5.00 4 ...