AD7933 Analog Devices, AD7933 Datasheet
AD7933
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AD7933 Summary of contents
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... Full shutdown mode: 2 μA maximum 28-lead TSSOP package GENERAL DESCRIPTION The AD7933/AD7934 are 10-bit and 12-bit, high speed, low power, successive approximation (SAR) analog-to-digital converters (ADCs). The parts operate from a single 2 5.25 V power supply and feature throughput rates up to 1.5 MSPS. ...
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... ADC Transfer Function............................................................. 17 Typical Connection Diagram ................................................... 18 Analog Input Structure.............................................................. 18 Analog Inputs ............................................................................. 19 Analog Input Selection .............................................................. 21 Reference ..................................................................................... 22 Parallel Interface......................................................................... 23 Power Modes of Operation ....................................................... 26 Power vs. Throughput Rate....................................................... 27 Microprocessor Interfacing....................................................... 27 Application Hints ........................................................................... 29 Grounding and Layout .............................................................. 29 Evaluating the AD7933/AD7934 Performance...................... 29 Outline Dimensions ....................................................................... 30 Ordering Guide .......................................................................... 30 Rev Page ...
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... SPECIFICATIONS AD7933 SPECIFICATIONS 2 5.25 V, internal/external V DD DRIVE unless otherwise noted. MAX Table 2. Parameter DYNAMIC PERFORMANCE 2 Signal-to-Noise + Distortion (SINAD) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) 2 Intermodulation Distortion (IMD) Second-Order Terms Third-Order Terms Channel-to-Channel Isolation 2 Aperture Delay ...
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... AD7933/AD7934 Parameter REFERENCE INPUT/OUTPUT 5 V Input Voltage REF 4 DC Leakage Current V Output Voltage REFOUT V Temperature Coefficient REFOUT V Noise REF V Output Impedance REF V Input Capacitance REF LOGIC INPUTS Input High Voltage, V INH Input Low Voltage, V INL Input Current Input Capacitance ...
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... V REF −0.3 to +0.7 −0.3 to +1.8 V ± REF V ± REF ± Rev Page AD7933/AD7934 = 25.5 MHz 1.5 MSPS; CLKIN SAMPLE Unit Test Conditions/Comments kHz sine wave IN dB min Differential mode dB min Single-ended mode dB min Differential mode dB min Single-ended mode dB max − ...
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... AD7933/AD7934 Parameter REFERENCE INPUT/OUTPUT 5 V Input Voltage REF DC Leakage Current V Output Voltage REFOUT V Temperature Coefficient REFOUT V Noise REF V Output Impedance REF V Input Capacitance REF LOGIC INPUTS Input High Voltage, V INH Input Low Voltage, V INL Input Current Input Capacitance LOGIC OUTPUTS ...
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... CLKIN low pulse width CLKIN high pulse width = (10 RISE FALL , quoted in the timing characteristics is the true bus relinquish time of the part and is independent of the 14 Rev Page AD7933/AD7934 = 25.5 MHz 1.5 MSPS; SAMPLE ) and timed from a voltage level of DD ...
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... AD7933/AD7934 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 5. Parameter V to AGND/DGND AGND/DGND DRIVE Analog Input Voltage to AGND Digital Input Voltage to DGND DRIVE DD Digital Output Voltage to AGND V to AGND REFIN AGND to DGND Input Current to Any Pin Except Supplies ...
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... Word/Byte Input. When this input is logic high, word transfer mode is enabled, and data is transferred to and from the AD7933/AD7934 in 10-bit words on Pin DB2 to Pin DB11 12-bit words on Pin DB0 to Pin DB11. When W/B is logic low, byte transfer mode is enabled. Data and the channel ID are transferred on Pin DB0 to Pin DB7, and Pin DB8/HBEN assumes its HBEN functionality ...
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... AGND Analog Ground. This is the ground reference point for all analog circuitry on the AD7933/AD7934. All analog input signals and any external reference signal should be referred to this AGND voltage. The AGND and DGND voltages should ideally be at the same potential and must not be more than 0.3 V apart, even on a transient basis. ...
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... Figure 5. AD7934 SINAD vs. Analog Input Frequency for Various Supply Voltages DRIVE 610 810 1010 500 600 700 800 600 700 800 900 1000 Rev Page AD7933/AD7934 0 4096 POINT FFT – SAMPLE – 49.62kHz IN SINAD = 70.94dB –30 THD = –90.09dB DIFFERENTIAL MODE –40 –50 – ...
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... AD7933/AD7934 4 SINGLE-ENDED MODE POSITIVE DNL 0 NEGATIVE DNL –1 0.25 0.50 0.75 1.00 1.25 1.50 V (V) REF Figure 9. AD7934 DNL vs. V REF DIFFERENTIAL MODE 10 SINGLE-ENDED MODE SINGLE-ENDED MODE DIFFERENTIAL MODE 0.5 1.0 1.5 2.0 V (V) REF Figure 10. AD7934 ENOB vs –0.5 DD –1 –1.5 DD –2.0 – ...
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... Pf is the power at frequency f in the ADC output the power at frequency f S Rev Page AD7933/AD7934 input range with −V REF biased about the V point the deviation of the first REF + 1 LSB) after the zero-code error has been adjusted out. ...
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... The AD7933/AD7934 is tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. In this case, the second-order terms are usually ...
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... The SEQ0 bit in the control register is used in conjunction with the SEQ1 bit to control the sequencer function (see Table 11). 0 RANGE This bit selects the analog input range of the AD7933/AD7934. If RANGE is set to 0, the analog input range extends from selected the analog input remains within the supply rails ...
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... ADD1 and ADD0, the channel address bits, in each prior write operation. This mode of operation reflects the normal operation of a multichannel ADC, without using the sequencer function, where each write to the AD7933/AD7934 selects the next channel for conversion Not used ...
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... ADC can cycle with each falling edge of CONVST . The analog input range for the AD7933/AD7934 × depending on the status of the RANGE bit in REF the control register ...
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... Figure 17. AD7933/AD7934 Ideal Transfer Characteristic with Twos Complement Output Coding and 2 × V TYPICAL CONNECTION DIAGRAM Figure 18 shows a typical connection diagram for the AD7933/AD7934. The AGND and DGND pins are connected together at the device for good noise suppression. If the internal reference is used, the V /V ...
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... V being preconditioned before it is applied to the AD7933/AD7934. In cases where the analog input amplitude is ±2.5 V, the 3R resistor can be replaced with a resistor of value R. The resultant voltage on the analog input of the AD7933/AD7934 is a signal ranging from this 1k case, the 2 × V +1.25V 0V – ...
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... When a conversion takes place, the common mode is rejected, resulting in a virtually noise-free signal of amplitude −V +V corresponding to the digital codes 1024 for the REF AD7933, and 0 to 4096 for the AD7934. If the 2 × V used, the input signal amplitude extends from − REF 3 ...
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... V– 10kΩ Figure 28. Dual Op Amp Circuit to Convert a Single-Ended Unipolar Signal into a Differential Signal Another method of driving the AD7933/AD7934 is to use the AD8138 differential amplifier. The AD8138 can be used as a single-ended-to-differential amplifier, or differential-to-differential amplifier. The device is as easy to use amp and greatly simplifies differential signal amplification and driving ...
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... The WR input must be kept high to ensure that the control register is not accidentally overwritten and the sequence interrupted. This pattern continues until the AD7933/AD7934 is written to. Figure 31 shows the flowchart of the consecutive sequence mode. POWER ON WRITE TO THE CONTROL REGISTER TO ...
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... DB0 TO DB11 WITH CS AND RD TIED LOW DB0 TO DB11 Figure 34. AD7933/AD7934 Parallel Interface—Conversion and Read Cycle Timing in Word Mode ( the end of the conversion, BUSY goes low and can be used to activate an interrupt service routine. The CS and RD lines are then activated in parallel to read the 10 bits or 12 bits of conversion data ...
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... HBEN/DB8 CS RD DB0 TO DB7 Figure 35. AD7933/AD7934 Parallel Interface—Read Cycle Timing for Byte Mode Operation ( The CS and RD signals are gated internally and the level is triggered active low. In either word mode or byte mode, CS and RD can be tied together as the timing specifications for t t are 0 ns minimum ...
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... HBEN/DB8 CS WR DB0 TO DB7 Figure 37. AD7933/AD7934 Parallel Interface—Write Cycle Timing for Byte Mode Operation ( Figure 36 shows the write cycle timing diagram of the AD7933/AD7934 in word mode. When operating in word mode, the HBEN input does not exist and only one write operation is required to write the word of data to the device ...
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... The track-and-hold also goes into hold at this point and remains in hold as long as the device is in shutdown. The AD7933/AD7934 remains in shutdown mode until the next rising edge of CONVST (see Point B in Figure 34 and Figure 38). In order to keep the device in shutdown for as long as possible, CONVST should idle low between conversions, as shown in Figure 38 ...
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... MICROPROCESSOR INTERFACING AD7933/AD7934 to ADSP-21xx Interface Figure 41 shows the AD7933/AD7934 interfaced to the ADSP-21xx series of DSPs as a memory-mapped device. A single wait state may be necessary to interface the AD7933 2.0 mA AD7934 to the ADSP-21xx, depending on the clock speed of DD the DSP. The wait state can be programmed via the data memory wait state control register of the ADSP-21xx (see the ADSP-21xx family User’ ...
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... Parallel interfaces between the AD7933/AD7934 and the TMS32020, TMS320C25 and TMS320C5x family of DSPs are shown in Figure 43. Select the memory-mapped address for the AD7933/AD7934 to fall in the I/O memory space of the DSPs. The parallel interface on the AD7933/AD7934 is fast enough to interface to the TMS32020 with no extra wait states. If high ...
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... CB designator, to demonstrate and evaluate the ac and dc performance of the AD7933/AD7934. The software allows the user to perform ac (fast Fourier transform) and dc (histogram of codes) tests on the AD7933/AD7934. The software and documentation are on the CD that ships with the evaluation board. Rev Page ...
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... AD7933BRU −40°C to +85°C AD7933BRU-REEL –40°C to +85°C AD7933BRU-REEL7 –40°C to +85°C 2 AD7933BRUZ –40°C to +85°C 2 AD7933BRUZ-REEL7 –40°C to +85°C AD7934BRU −40°C to +85°C AD7934BRU-REEL –40°C to +85°C AD7934BRU-REEL7 –40°C to +85°C 2 AD7934BRUZ – ...
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... NOTES Rev Page AD7933/AD7934 ...
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... AD7933/AD7934 NOTES ©2005–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03713-0-2/07(B) Rev Page ...