AD6640ST Analog Devices, AD6640ST Datasheet
AD6640ST
Related parts for AD6640ST
AD6640ST Summary of contents
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... Units are packaged in a 44-terminal Plastic Thin Quad Flatpack (TQFP) specified from – +85 C. REV. 0 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 which may result from its use ...
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AD6640–SPECIFICATIONS DC SPECIFICATIONS ( Parameter RESOLUTION ACCURACY No Missing Codes Offset Error Gain Error 1 Differential Nonlinearity (DNL) 1 Integral Nonlinearity (INL) TEMPERATURE DRIFT Offset Error Gain Error POWER SUPPLY REJECTION (PSRR) 2 REFERENCE OUT ...
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SWITCHING SPECIFICATIONS Parameter (Conditions) Maximum Conversion Rate 2 Minimum Conversion Rate Aperture Delay ( Aperture Uncertainty (Jitter) 3 ENCODE Pulsewidth High ENCODE Pulsewidth Low Output Delay ( +3.3 V/5 NOTES 1 All switching ...
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... Model Temperature Range AD6640AST – +85 C (Ambient) AD6640ST/PCB 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. Although the AD6640 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...
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Pin No. Name 1, 2, 36, 37, 40 ENCODE 4 ENCODE 5, 6, 13, 14, 17, 18, 21, 22, 24, 34, 35, 38, 39 GND 7 AIN AIN REF 10 C1 11, 12, ...
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AD6640 DEFINITION OF SPECIFICATIONS Analog Bandwidth (Small Signal) 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 a differential crossing ...
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ANALOG INPUTS ENCODE INPUTS (ENCODE) DIGITAL OUTPUTS AIN BUF 450 V CL BUF 450 AIN BUF V CL Figure 2. Analog Input Stage 17k ENCODE TIMING R2 ...
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AD6640 –Typical Performance Characteristics 100 120 dc 6.5 13.0 19.5 FREQUENCY – MHz Figure 7. Single Tone at 2.2 MHz ...
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ENCODE = 65MSPS AIN = 15.0, 16.0MHz NO DITHER 100 120 dc 6.5 13.0 19.5 FREQUENCY – MHz Figure 13. Two Tones at 15.0 MHz & 16.0 MHz 100 90 dBFS 80 70 ENCODE = ...
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AD6640 0 ENCODE = 65MSPS AIN = 19.5MHz @ –36dBFS –20 NO DITHER –40 –60 –80 –100 –120 dc 65 13.0 19.5 FREQUENCY – MHz Figure 19. 16K FFT without Dither 100 90 ENCODE = 65MSPS 80 AIN = 19.5MHz ...
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THEORY OF OPERATION The AD6640 analog-to-digital converter (ADC) employs a two- stage subrange architecture. This design approach ensures 12-bit accuracy, without the need for laser trim, at low power. As shown in the functional block diagram, the AD6640 has complementary ...
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AD6640 T1–1T SINE SOURCE R Figure 29. Sine Source – Differential Encode If a low jitter ECL clock is available, another option is to ac- couple a differential ECL signal to the encode input pins as shown below. The capacitors ...
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The addition of small value resistors between the AD9631 and the AD6640 will prevent oscillation due to the capacitive input of the ADC. AD9631 62 SIGNAL SOURCE 467 78 350 1000 OP279 OP279 (1/2) (1/2) ...
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... AD6640 data sample, latches the previous data at the con- verter output, and strobes the external data register over J3. NOTE: Power and ground must be applied power the digital logic section of the evaluation board. Table I. AD6640ST/PCB Bill of Material Description Banana Jack Ceramic Chip Capacitor 0805, 0.1 F ...
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... DUT D3 28 AD6640 (LSB GND 348 CONNECT 348 C15 C16 0.1 F 0.1 F Figure 36. AD6640ST/PCB Schematic –15– AD6640 74LCX574 ( 348 348 348 348 ...
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... AD6640 Figure 37. AD6640ST/PCB Top Side Silkscreen Figure 38. AD6640ST/PCB Bottom Side Silkscreen NOTE: Evaluation boards are often updated, consult factory for latest version. Figure 39. AD6640ST/PCB Top Side Copper Figure 40. AD6640ST/PCB Bottom Side Copper (Positive) –16– REV. 0 ...
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... Figure 41. AD6640ST/PCB Ground Layer (Negative) REV. 0 Figure 42. AD6640ST/PCB “Split” Power Layer (Negative) –17– AD6640 ...
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... Moreover, the tuning and filtering characteristics can be changed through software. Since software SHARC is a registered trademark of Analog Devices, Inc. is used for demodulation, different routines may be used to demodulate different standards such as AM, FM, GMSK or any other desired standard ...
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PRESELECT LNA FILTER PASSBAND LO DRIVE 1900MHz M/N PLL SYNTHESIZER REF IN 65.00MHz REFERENCE CLOCK System Requirements Figure 46 shows a typical wideband receiver subsystem based around the AD6640. This strip consists of a wideband IF filter, amplifier, ADC, latches, ...
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AD6640 faster the signal is digitized, the wider the distribution of noise. Since the integrated noise must remain constant, the actual noise floor is lowered each time the sample rate is doubled. The effective noise density for ...
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The simplest method for generating dither is through the use of a noise diode (Figure 48). In this circuit, the noise diode NC202 generates the reference noise that is gained up and driven by the AD600 and OP27 amplifier chain. ...
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AD6640 IF Sampling, Using the AD6640 as a Mix-Down Stage Since performance of the AD6640 extends beyond the baseband region into the third Nyquist zone, the converter has many uses as a mix-down converter in both narrowband and wideband applications. ...
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EIGHT WIDEBAND FRONT ENDS ANTENNA 1 COMMON LO ANTENNA 2 ANTENNA 3 ANTENNA 4 ANTENNA 5 ANTENNA 6 ANTENNA 7 ANTENNA 8 Figure 52. Receive Chain for a Phased Array Cellular Base Station with Eight Antennas and 32 Channels REV. ...
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AD6640 AD6640AST OUTLINE DIMENSIONS Dimensions shown in inches and (mm) 44-Terminal Plastic Thin Quad Flatpack (ST-44) 0.063 (1.60) MAX 0.472 (12.00) SQ 0.030 (0.75) 0.018 (0.45 SEATING PLANE TOP VIEW (PINS DOWN 0.006 (0.15) 0.002 (0.05) ...