AD6645/PCB Analog Devices, AD6645/PCB Datasheet
AD6645/PCB
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AD6645/PCB Summary of contents
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... Rev. D Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. ...
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AD6645 TABLE OF CONTENTS www.DataSheet4U.com Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 DC Specifications ......................................................................... 3 Digital Specifications ................................................................... 4 AC ...
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SPECIFICATIONS www.DataSheet4U.com DC SPECIFICATIONS 3 and MIN MAX Table 1. Parameter Temp RESOLUTION ACCURACY No Missing Codes Full Offset Error Full Gain Error Full Differential Nonlinearity (DNL) Full Integral ...
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AD6645 DIGITAL SPECIFICATIONS www.DataSheet4U.com 3 and MIN MAX Table 2. Parameter ENCODE INPUTS (ENCODE, ENCODE) 1 Differential Input Voltage Differential Input Resistance Differential Input Capacitance LOGIC OUTPUTS (D13 to ...
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Parameter WORST HARMONIC (FOURTH OR HIGHER) Analog Input @ −1 dBFS TWO-TONE SFDR 2, 3 TWO-TONE IMD REJECTION F1 −7 dBFS ANALOG INPUT BANDWIDTH 1 Analog input signal power swept from −10 dBFS to −100 dBFS. 2 ...
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AD6645 www.DataSheet4U.com Parameter DATA-READY (DRY 4 )/DATA(D13:0),, OVR Data-Ready to DATA Delay (Hold Time) 50% Duty Cycle Data-Ready to DATA Delay (Setup Time) 50% Duty Cycle APERTURE DELAY APERTURE UNCERTAINTY (JITTER) 1 Several timing parameters are a function of t ...
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ABSOLUTE MAXIMUM RATINGS www.DataSheet4U.com Table 5. Parameter Electrical AV Voltage CC DV Voltage CC Analog Input Voltage Analog Input Current Digital Input Voltage Digital Output Current Environmental Operating Temperature Range (Ambient) AD6645-80 AD6645-105 Maximum Junction Temperature Lead Temperature (Soldering, 10 ...
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AD6645 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS www.DataSheet4U.com ENCODE ENCODE NOTES 1. DNC = DO NOT CONNECT. 2. EXPOSED PAD. CONNECT THE EXPOSED PAD TO GND. Table 7. Pin Function Descriptions Pin Number Mnemonic 1, 33 ...
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TYPICAL PERFORMANCE CHARACTERISTICS www.DataSheet4U.com 0 ENCODE = 80MSPS –10 AIN = 2.2MHz @ –1dBFS SNR = 75.0dB –20 SFDR = 93.0dBc –30 –40 –50 –60 –70 –80 3 – –100 6 4 –110 –120 –130 ...
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AD6645 75.5 www.DataSheet4U.com 75 –40°C 74 +85°C 74 +25°C 73.5 73.0 72.5 ENCODE = 80MSPS @ AIN = –1dBFS TEMP = –40°C, +25°C, +85°C 72 FREQUENCY (MHz) Figure 10. ...
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ENCODE = 80MSPS –10 AIN = 30.5MHz, 31.5MHz (–7dBFS) –20 NO DITHER –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 –130 FREQUENCY (MHz) Figure 16. Two-Tone SFDR @ 30.5 MHz ...
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AD6645 0 www.DataSheet4U.com ENCODE = 80.0MSPS –10 AIN = 30.5MHz @ –29.5dBFS NO DITHER –20 –30 –40 –50 –60 –70 –80 2 –90 6 –100 3 –110 5 –120 –130 FREQUENCY (MHz) Figure 22. ...
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ENCODE = 76.8MSPS –10 AIN = 2W-CDMA @ 59.6MHz –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 –130 FREQUENCY (MHz) Figure 28. Two W-CDMA Carriers @ 59.6 MHz, Encode ...
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AD6645 EQUIVALENT CIRCUITS www.DataSheet4U.com AIN BUF 500Ω BUF 500Ω AIN BUF V CL Figure 32. Analog Input Stage LOADS 10kΩ ENCODE 10kΩ LOADS Figure 33. Encode ...
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TERMINOLOGY www.DataSheet4U.com Analog Bandwidth The analog input frequency at which the spectral power of the fundamental frequency (as determined by the FFT analysis) is reduced by 3 dB. Aperture Delay The delay between the 50% point of the rising edge ...
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AD6645 Spurious-Free Dynamic Range (SFDR) www.DataSheet4U.com The ratio of the rms signal amplitude to the rms value of the peak spurious spectral component. The peak spurious component may or may not be a harmonic. May be reported in dBc (that ...
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THEORY OF OPERATION www.DataSheet4U.com The AD6645 ADC employs a three-stage subrange architecture. This design approach achieves the required accuracy and speed while maintaining low power and small die size. As shown in the functional block diagram (see Figure 1), the ...
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AD6645 This limits the amount of dynamic current from the A/D www.DataSheet4U.com flowing back into the secondary of the transformer. The 50 Ω impedance matching can also be incorporated on the secondary side of the transformer, as shown in the ...
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LAYOUT INFORMATION www.DataSheet4U.com The schematic of the evaluation board (see Figure 43) represents a typical implementation of the AD6645. A multi- layer board is recommended to achieve best results highly recommended that high quality, ceramic chip capacitors be ...
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... AD6645 Table 9. AD6645/PCB Bill of Materials www.DataSheet4U.com Quantity Quantity 80 MSPS 105 MSPS Reference PCB 4 4 C1, C2, C31, C38 C10, C16, 1 C30 , C32 9 9 C4, C15, C22 to C26, C29, (C33 (C34) , C39 (C5, C6 C11 to C14, C17 to C21, C40 ...
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Quantity Quantity www.DataSheet4U.com 80 MSPS 105 MSPS Reference (U8 AC-coupled AIN is standard: R3, R4, R5, R8, and U3 are not installed. If dc-coupled AIN is ...
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AD6645 www.DataSheet4U.com ...
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Figure 44. Top Signal Level Figure 45. 5.0 V Plane Layer 3 and 3.3 V Plane Layer 4 Figure 46. Ground Plane Layer 2 and Ground Plane Layer 5 Figure 47. Bottom Signal Layer Rev Page 23 ...
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... AD6645ASQZ-105 −10°C to +85°C 1 AD6645ASVZ-105 −10°C to +85°C 1 AD6645-80/PCBZ 1 AD6645-105/PCBZ RoHS Compliant Part. ©2002–2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02647-0-10/08(D) 12.20 2.65 12.00 SQ 2.50 (4 PLCS) 11.80 2. ...