ad8321 Analog Devices, Inc., ad8321 Datasheet
ad8321
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ad8321 Summary of contents
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... ATTENUATOR CORE VIN– DATA LATCH DATA SHIFT REGISTER DATA SHIFT REGISTER DATEN CLK SDATA The AD8321 is packaged in a low cost 20-lead SOIC, operates from a single +9 V supply, and has an operational temperature range of –40∞C to +85∞C. –40 –50 –60 –70 – ...
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... AD8321–SPECIFICATIONS Parameter INPUT CHARACTERISTICS Specified AC Voltage Noise Figure Input Resistance Input Capacitance GAIN CONTROL INTERFACE Gain Range Maximum Gain Minimum Gain Gain Scaling Factor OUTPUT CHARACTERISTICS Bandwidth (–3 dB) Bandwidth Roll-Off Bandwidth Peaking Output Offset Voltage Output Noise Spectral Density Output Noise Temperature Sensitivity 0 £ T ...
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... GAIN TRANSFER (G1) T OFF T GS PEDESTAL Figure 2. Serial Interface Timing VALID DATA BIT MSB MSB CLK Figure 3. SDATA Timing –3– AD8321 Typ Max 5.0 0.8 20 –100 190 – ns MHz unless otherwise noted.) F CLK Typ Max 10 GAIN TRANSFER (G2) ...
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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD8321 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... OU T MAX GAIN) – FUNDAMENTAL FREQUENCY – MHz Figure 10. Third Order Harmonic Distortion vs. Frequency for Various Input Levels REV. A Typical Performance Characteristics–AD8321 30 20 71D 10 0 46D –10 23D –20 –30 00D –40 1000 0 100 FREQUENCY – MHz Figure 5. AC Response – ...
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... AD8321 34 MAX GAIN P = 11dBm OUT 10pF 0pF 20pF 50pF 100 FREQUENCY – MHz Figure 13. AC Response for Various Capacitor Loads 7.5mV V OUT p-p IN MAX GAIN tr(CLK) = 3ns CLK DATEN 5V 150ns Figure 16. Clock Feedthrough 1.5V MAX GAIN ...
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... AD8321’s digital decode sec tion when the DATEN input is taken high. The gain of the AD8321 is linear in steps of 0.7526 dB. The gain transfer function starts at –27.43 dB (at decimal code 0) and increases 0.7526 dB/LSB. The gain increases up to decimal code 71 ...
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... As a result, the AD8321 line driver is required to vary its output applying attenuation or gain as needed so that all signals arriving at the central office are of the same amplitude. ...
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... Figure 25. If the BYP1 and/or BYP2 voltages are used externally, they should be buffered. External back termination resistors are not required when using the AD8321. The output impedance of the AD8321 and is maintained dynamically. This on chip back termination is maintained regardless of whether the amplifier is in forward transmit mode or reverse powered down mode ...
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... AD8321 Varying the Gain and SPI Programming The gain of the AD8321 can be varied over a range from approximately – +26 dB, in increments of approximately 0.7526 dB per LSB. Programming the gain of the AD8321 is accomplished using conventional Serial Peripheral Interface or SPI protocol. Three digital lines, DATEN, CLK and SDATA, are used to stream eight bits of data into the serial shift register of the AD8321 ...
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... These graphs indicate the worst harmonic levels exhibited over the entire output range of the AD8321 (i.e., – +26 dB). Figures 9 and 10 are useful when it is necessary to determine inband harmonic levels (5 MHz to 42 MHz or 5 MHz to 65 MHz). Harmonics that ...
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... AD8321-EVAL circuit and is controlled by the check box on the control panel portrayed in Figure 31. AD8321 This feature is intended to remove the output of the AD8321 from the VOUT port prior to using the “Power Up” and “Power Down” feature described above. This application circuit may be used to reduce any transients created between bursts to DOCSIS compliant levels ...
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... R8 1k� V1 P1–8 C16 1000pF R9 1k� V2 P1–7 C17 1000pF Figure 28. AD8321-EVAL Schematic of Single-Ended Inverting Input, Upstream PA Driver Solution Using AD8321, Matching Attenuator and Alpha Industries AS128-73 RF Switch REV. A C10 C12 1000pF 3 18 C11 4 17 ...
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... AD8321 EVALUATION BOARD FEATURES AND OPERATION Figure 29. Evaluation Board Software Installation Figure 30. Evaluation Board Control Software –14– REV. A ...
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... Figure 31. Screen Display of Windows-Based Control Software REV. A –15– AD8321 ...
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... AD8321 Figure 32. Evaluation Board Silkscreen (Component Side) –16– REV. A ...
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... Figure 33. Evaluation Board Layout (Component Side) REV. A Figure 34. Evaluation Board Layout (Solder Side) –17– AD8321 ...
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... AD8321 AD8321 Evaluation Board Rev. B SINGLE- ENDED INVERTING INPUT March 17, 1999 Qty. Description 1350 size tantalum chip capacitor 2 0 1206 size ceramic chip capacitor 14 3 1,000 1206 size ceramic chip capacitor 82 1/8 W. 1206 size chip resistor 1/8 W. 1206 size chip resistor ...
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... Revision History Location 6/05—Data Sheet Changed from REV REV. A. Changes to ORDERING GUIDE ....................................................................................................................................................4 Updated OUTLINE DIMENSIONS.............................................................................................................................................19 REV. A OUTLINE DIMENSIONS 20-Lead Standard Small Outline Package [SOIC_W] Wide Body (R-20) Dimensions shown in millimeters and (inches) –19– AD8321 Page ...
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