AD6645ASQ-80 Analog Devices Inc, AD6645ASQ-80 Datasheet
AD6645ASQ-80
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AD6645ASQ-80 Summary of contents
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FEATURES SNR = 75 dB MHz 105 MSPS IN SNR = 72 dB, f 200 MHz 105 MSPS IN SFDR = 89 dBc MHz 105 MSPS IN 100 dBFS multitone ...
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AD6645 TABLE OF CONTENTS 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 Specifications ...
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... POWER CONSUMPTION Full 1 VREF is provided for setting the common-mode offset of a differential amplifier, such as the buffered if used to drive additional circuit functions. 2 Specified for dc supplies with linear rise time characteristics. at rated speed grade, unless otherwise noted. AD6645ASQ-80/AD6645ASV-80 Test Level Min Typ 14 II Guaranteed II − ...
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... Temp Level Min Typ Full IV 0.4 25° 25°C V 2.5 CMOS Full II 2.85 DV − Full II 0.2 Twos complement Full AD6645ASQ-80/ Test AD6645ASV-80 Temp Level Min Typ 25°C V 75.0 Full II 72.5 74.5 25°C I Full II 72.0 73.5 25°C V 73.0 25°C V 72.0 25°C V 75.0 Full II 72 ...
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... V 90.0 25°C V 88.0 25°C V 100 25°C V 100 25°C V 25° 25°C V 270 and T at rated speed grade, unless otherwise noted. MIN MAX AD6645ASQ-80/ Test AD6645ASV-80 Symbol Temp Level Min Typ Full II 80 Full IV Full IV 5.625 Full V 6.25 Full IV 5.625 Full V 6 ...
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... DRY is an inverted and delayed version of the encode clock. Any change in the duty cycle of the clock will correspondingly change the duty cycle of DRY. 5 Data-ready to DATA Delay (t and calculated relative to rated speed grade and is dependent on t H_DR S_DR AIN ENCODE, ENCODE t E_RL D[13:0], OVR DRY AD6645ASQ-80/ Test AD6645ASV-80 Symbol Temp Level Min t Full V H_DR Full V 6.6 ...
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ABSOLUTE MAXIMUM RATINGS 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 sec) ...
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AD6645 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 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 10, ...
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TYPICAL PERFORMANCE CHARACTERISTICS 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 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. Signal-to-Noise ...
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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 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. 1 ...
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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 AIN BUF 500Ω BUF 500Ω AIN BUF V CL Figure 32. Analog Input Stage LOADS 10kΩ ENCODE 10kΩ LOADS Figure 33. Encode Inputs ...
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TERMINOLOGY 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 of ...
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AD6645 Spurious-Free Dynamic Range (SFDR) 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 is, ...
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THEORY OF OPERATION 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 AD6645 ...
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AD6645 This limits the amount of dynamic current from the A/D 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 evaluation ...
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LAYOUT INFORMATION 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 used ...
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... Samtec TSW-120-08-T-D-RA Johnson Components 142-0701-201 Coilcraft 1008CT-040X-J Panasonic ERJ-2RKF1000 Panasonic ERJ-8ENF60R4V Panasonic ERJ-6ENF4990V Panasonic ERJ-6ENF25R5V Panasonic ERJ-6ENF66R5V Panasonic ERJ-6ENF1000V Panasonic ERJ-2RKF1780X Panasonic ERJ-6ENF49R9V Panasonic EXB2HV101JV Mini-Circuits ADT4-1WT Analog Devices AD6645ASQ/ASV-80 Analog Devices AD6645ASQ/ASV-105 Fairchild 74LCX574WM Analog Devices AD8138AR Fairchild NC7SZ32 ...
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Quantity Quantity 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 required, ...
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AD6645 ...
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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 of ...
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... MAX COPLANARITY VIEW A ROTATED 90 ° CCW ORDERING GUIDE Model Temperature Range AD6645ASQ-80 −40°C to +85°C 1 AD6645ASQZ-80 −40°C to +85°C 1 AD6645ASVZ-80 −40°C to +85°C AD6645ASQ-105 −10°C to +85°C 1 AD6645ASQZ-105 −10°C to +85°C ...