ad8348-eval Analog Devices, Inc., ad8348-eval Datasheet
ad8348-eval
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ad8348-eval Summary of contents
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... W-CDMA/CDMA/GSM/NADC Wireless local loop LMDS GENERAL DESCRIPTION The AD8348 is a broadband quadrature demodulator with an integrated intermediate frequency (IF), variable gain amplifier (VGA), and integrated baseband amplifiers suitable for use in communications receivers, performing quadrature demodulation from IF directly to baseband frequencies. The baseband amplifiers ...
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... AD8348 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Equivalent Circuits ........................................................................... 9 Typical Performance Characteristics ........................................... 11 VGA and Demodulator ............................................................. 11 Demodulator Using MXIP and MXIN.................................... 14 Final Baseband Amplifiers ........................................................ 15 VGA/Demodulator and Baseband Amplifier......................... 16 Theory of Operation ...
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... MHz) vs. temperature vs. baseband frequency ( MHz) Maximum gain, from 200 Ω source 380 MHz IF Shunt from IMXO, QMXO to VCMO Shunt from IMXO, QMXO to VCMO Rev Page AD8348 (IFIP and MXIP/MXIN) = 200 Ω, unless S Min Typ Max 100 2000 50 1000 75 − ...
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... AD8348 Parameter IF FRONT END WITHOUT VGA Input Impedance Conversion voltage Gain 3 dB Output Bandwidth IF Gain Flatness Input 1 dB Compression Point (P1dB) Third-Order Input Intercept (IIP3) LO Leakage Demodulation Bandwidth Quadrature Phase Error I/Q Amplitude Imbalance Noise Figure (Double Sideband) I/Q BASEBAND AMPLIFIER Gain Bandwidth ...
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... Time for final baseband amplifiers to be within 90% of final amplitude Time for supply current to be <10% of enabled value VPOS1, VPOS2, VPOS3 ENBL ENBL Rev Page AD8348 Min Typ Max Unit − ...
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... AD8348 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage on VPOS1, VPOS2, VPOS3 Pins LO Input Power IF Input Power Internal Power Dissipation θ JA Maximum Junction Temperature Operating Temperature Range Storage Temperature Range Lead Temperature (Soldering, 60 sec) ESD CAUTION 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 ...
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... IFIP 11 18 VPOS2 12 17 IOFS 13 16 VREF 14 15 Figure 2. 28-Lead TSSOP Pin Configuration = 57.6 Ω. This provides a 200 Ω source impedance to the IF input. However, the AD8348 Rev Page LOIN COM1 QOPN QOPP ENVG QAIN COM3 QMXO VPOS3 MXIN MXIP VGIN QOFS ENBL = 174 Ω ...
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... AD8348 Pin No. Mnemonic Description 15 ENBL Chip Enable Input. Active high. Threshold is equal VGIN Gain Control Input. The voltage on this pin controls the gain on the IF VGA. The gain control voltage range is from 0 1.2 V and corresponds to a conversion gain range from +25 −18.5 dB. This is the gain to the output of the mixers (that is, IMXO and QMXO) ...
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... COM3 Figure 4. Circuit B VPOS3 VCMO COM3 Figure 5. Circuit C VPOS3 IOPP, IOPN, QOPP, QOPN VCMO Rev Page VPOS3 IAIN, QAIN, VGIN, ENBL, ENVG COM3 Figure 6. Circuit D VPOS2 IFIP IFIN COM3 Figure 7. Circuit E VPOS3 50µA MAX IOFS, QOFS COM3 Figure 8. Circuit F AD8348 ...
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... AD8348 VPOS2 VREF COM2 Figure 9. Circuit G COM3 Figure 10. Circuit H VPOS3 IMXO, QMXO Rev Page VPOS3 MXIP MXIN COM3 Figure 11. Circuit I ...
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... IF FREQUENCY (MHz) Figure 17. Gain vs VGIN = 1 Temperature = −40°C, +25°C, +85°C AD8348 –1 –2 –3 –4 –5 –6 1.1 1 900 MHz, IF 5V, 0.2V, +85°C 800 ...
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... AD8348 27 5V, 0.2V, +25° 2.7V, 0.2V, +85°C 24 2.7V, 0.2V, +25°C 23 2.7V, 0.2V, –40°C 22 5V, 0.2V, +85° BASEBAND FREQUENCY (MHz) Figure 18. Gain vs VGIN = 0 380 MHz Temperature = −40°C, +25°C, +85°C –17 2.7V, 1.2V, +85°C –20 2.7V, 1.2V, +25°C 5V, 1.2V, +25°C –23 5V, 1.2V, –40°C – ...
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... Figure 28. Noise Figure and IIP3 vs. VGIN, Temperature = 25°C, POS 850 950 – MHz Figure 29. Noise Figure and Quadrature Phase Error IMXO/QMXO vs. LO Input BB Level, Temperature = 25°C, VGIN = 0 Rev Page AD8348 NF IIP3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 VGIN ( 380 MHz MHz 2 POS ...
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... AD8348 DEMODULATOR USING MXIP AND MXIN 11.0 10.5 TEMP = –40°C, V POS 10.0 TEMP = –40°C, V 9.5 TEMP = +25° POS 9.0 TEMP = +25° 2.7V POS 8.5 TEMP = +85° POS 8.0 100 200 300 400 500 600 IF FREQUENCY (MHz) Figure 30. Mixer Gain vs 2 POS Temperature = −40°C, +25°C, +85°C – ...
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... BASEBAND FREQUENCY (MHz VREF = 2 VCMO POS Temperature = −40°C, +25°C, +85° 100 1000 10000 FREQUENCY (kHz) Figure 36. Noise Spectral Density AD8348 170 190 100000 ...
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... AD8348 VGA/DEMODULATOR AND BASEBAND AMPLIFIER 2.0 1.5 1.0 2.7V, 0.2V, –40°C 0.5 0 2.7V, 0.2V, +85°C –0.5 5V, 0.2V, +25°C –1.0 –1.5 –2.0 100 200 300 400 500 600 IF FREQUENCY (MHz) Figure 37. Quadrature Phase Error vs VGIN = 0 Temperature = −40°C, +25°C, +85°C 2.0 1.5 2.7V, 0.7V, +25°C 1.0 2.7V, 0.7V, –40°C 5V, 0.7V, –40°C 0.5 0 –0.5 5V, 0.7V, +25° ...
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... RETURN LOSS LO INPUT, THROUGH BALUN WITH 60.4Ω IN SHUNT BETWEEN LOIP/LOIN FREQUENCY APPLIED TO LOIP/LOIN (MHz) Through Balun, with Termination Resistor 2. –40 –30 –20 – TEMPERATURE (°C) Figure 47. Supply Current vs. Temperature AD8348 ...
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... The amplifiers use voltage feedback to linearize the gain over the demodulation bandwidth. These amplifiers can be used to maximize the dynamic range at the input of an ADC following the AD8348. The input to the baseband amplifiers, IAIN (QAIN), feeds into the base of a bipolar transistor with an input impedance of roughly 50 kΩ ...
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... The feedback loop will be broken ac-coupled baseband filter is placed between the mixer outputs and the baseband amplifier inputs ac-coupled filter is implemented, the user must handle the offset compensation via some external means. Rev Page AD8348 ...
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... Figure 49. Basic Connections Schematic POWER SUPPLY The voltage supply for the AD8348, between 2.7 V and 5 V, should be provided to the +VPOSx pins, and ground should be connected to the COMx pins. Each supply pin should be decoupled separately using two capacitors whose recommended values are 100 pF and 0.1 μ ...
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... To achieve maximum voltage swing from the baseband amplifiers, VCMO should be driven at 2.25 V; this allows a swing p-p differential (3.5 V p-p single-ended). INTERFACING TO DETECTOR FOR AGC OPERATION The AD8348 can be interfaced with a detector such as the AD8362 rms-to-dc converter to provide an automatic signal- leveling function for the baseband outputs. MXIN ...
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... IFIP POWER INPUT (dBm, Z Figure 56. AD8348 Baseband Amplifier Output vs. IF Input Power with AD8362 AGC Loop BASEBAND FILTERS Baseband low-pass or band-pass filtering can be conveniently performed between the mixer outputs (IMXO and QMXO) and the input to the baseband amplifiers. Consideration should be given to the output impedance of the mixers (40 Ω ...
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... ADI also offers the ADF4360 fully integrated synthesizer and VCO on a single chip that offers differential outputs for driving the local oscillator input of the AD8348. This means that the user can eliminate the use of a balun for single-ended-to-differential conversions. The ADF4360 comes as a family of chips with six operating frequency ranges ...
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... VREF through LK11. If desired, the dc bias level can be changed by removing LK11 and driving a dc voltage onto the VCMO test point. J21 T21 ETC1-1- C21 C22 R21 1000pF 1000pF 60.4Ω AD8348 LOIP LOIN 1 28 VPOS1 COM1 2 27 IOPN QOPN 3 26 IOPP QOPP 25 4 R3I 49.9Ω ...
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... Figure 61. Evaluation Board Top Layer Figure 62. Evaluation Board Top Silkscreen Rev Page AD8348 ...
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... AD8348 Figure 63. Evaluation Board Bottom Layer Figure 64. Evaluation Board Bottom Silkscreen Rev Page ...
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... L pad that presents a 50 Ω termination to the driving source. This L pad introduces an 11.46 dB loss in the input signal path and should be taken into consideration when calculating the gain of the AD8348. MXIP, MXIN, Mixer inputs: These inputs can be configured for either differential or single-ended operation. ...
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... AD8348ARU-REEL7 −40°C to +85°C 1 AD8348ARUZ −40°C to +85°C AD8348ARUZ-REEL7 1 −40°C to +85°C AD8348-EVAL Pb-free part. ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 9.80 9.70 9. ...