AD7329 Analog Devices, AD7329 Datasheet
AD7329
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AD7329 Summary of contents
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... The analog input channels on the AD7329 can be programmed to be single-ended, true differential, or pseudo differential. The ADC contains a 2.5 V internal reference. The AD7329 also allows for external reference operation reference is applied to the REF ...
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... Autoshutdown Mode (PM1 = 1, PM0 = 0) ............................. 33 Autostandby Mode (PM1 = 0, PM0 =1) ................................. 33 Power vs. Throughput Rate ....................................................... 34 Serial Interface ................................................................................ 35 Microprocessor Interfacing ........................................................... 36 AD7329 to ADSP-21xx .............................................................. 36 AD7329 to ADSP-BF53x ........................................................... 36 Applications Information .............................................................. 37 Layout and Grounding .............................................................. 37 Power Supply Configuration .................................................... 37 Outline Dimensions ....................................................................... 38 Ordering Guide .......................................................................... 38 and I ...
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... Up to 100 kHz ripple frequency; see Figure 17 − see Figure 14 20 MHz 1.5 MHz At 0.1 dB Rev Page 2.5 V internal/external, f REF SCLK + and MUX − is connected directly to IN OUT = 50 kHz sine wave IN on unselected channels up to 100 kHz; IN AD7329 = 20 MHz, ...
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... AD7329 1 Parameter Min 4 DC ACCURACY Resolution 13 No Missing Codes 12-bit plus sign (13 bits) 11-bit plus sign (12 bits) 2 Integral Nonlinearity 2 Differential Nonlinearity Offset Error Offset Error Match 2, 5 Gain Error 2, 5 Gain Error Match 2, 6 Positive Full-Scale Error 2, 6 Positive Full-Scale Error Match ...
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... When in hold, all ranges, single ended All ranges, single ended All ranges, single ended 2 DRIVE I = 200 μA SOURCE I = 200 μA SINK Coding bit set control register Coding bit set control register AD7329 ...
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... AD7329 1 Parameter Min CONVERSION RATE Conversion Time Track-and-Hold Acquisition Time 2, 3 Throughput Rate POWER REQUIREMENTS − 2 2.7 DRIVE Normal Mode (Static) Normal Mode (Operational and I CC DRIVE Autostandby Mode (Dynamic and I CC DRIVE Autoshutdown Mode (Static) ...
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... SEL2 Figure 2. Serial Interface Timing Diagram Rev Page 2.5 V internal/external, T REF + is connected directly to ADC OUT ns, the mark-space ratio must be limited to 50:50 QUIET DB1 DB0 THREE-STATE LSB 0 AD7329 = MAX + and MUX − is OUT ...
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... ESD 1 If the analog inputs are driven from alternative V Schottky diodes should be placed in series with the V the AD7329 (see the Power Supply Configuration section). 2 Transient currents 100 mA do not cause SCR latch-up. Stresses above those listed under Absolute Maximum Ratings Rating may cause permanent damage to the device ...
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... Alternatively, the internal reference can be disabled and an external reference can be applied to this input. On power-up, the external reference mode is the default condition (see the Reference section Analog Supply Voltage, 2 5.25 V. This is the supply voltage for the ADC core on the AD7329. This supply CC should be decoupled to AGND Positive Power Supply Voltage ...
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... Negative Multiplexer Output. This pin allows access to the on-chip track-and-hold. The voltage applied to this OUT pin is still a high voltage signal when the AD7329 is in differential mode. When the AD7329 is in single-ended mode, this signal is AGND, and MUX pseudo differential mode, a small dc voltage appears at this pin, and this pin should be tied to the ADC ...
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... RANGE –0.8 +INL = +0.87LSB –INL = –0.49LSB –1.0 0 1024 2048 3072 4096 5120 6144 512 1536 2560 3584 4608 5632 CODE Figure 9. Typical INL for Single-Ended Mode AD7329 7168 8192 6656 7680 7168 8192 6656 7680 = 5V = –15V 7168 8192 6656 7680 ...
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... AD7329 – DRIVE V = 12V –12V DD SS – 25° 1MSPS S –60 INTERNAL REFERENCE AD8021 BETWEEN MUX OUT+ AND ADC PINS –65 IN+ – +10V RANGE –75 –80 –85 –90 –95 10 100 ANALOG INPUT FREQUENCY (kHz) Figure 10. THD vs. Analog Input Frequency for Single-Ended Mode – ...
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... AND ADC PINS 1000Ω 600Ω 100Ω 50Ω IN ±2.5V RANGE R = 4000Ω 1000Ω 600Ω 100Ω 50Ω IN 100 ANALOG INPUT FREQUENCY (kHz) True Differential Mode AD7329 + OUT ±19 1200 1000 ...
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... AD7329 –50 SINGLE-ENDED MODE V = 12V –12V DD SS – DRIVE INTERNAL REFERENCE AD8021 BETWEEN MUX + OUT –60 AND ADC + PINS IN –65 –70 –75 –80 –85 –90 10 100 ANALOG INPUT FREQUENCY (kHz) Figure 22. THD vs. Analog Input Frequency for Various Source Impedances, Single-Ended Mode – ...
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... N-bit converter with a sine wave input is given by Signal to (Noise + Distortion) = (6. 1.76) dB For a 13-bit converter, this is 80.02 dB. Total Harmonic Distortion Total harmonic distortion (THD) is the ratio of the rms sum of harmonics to the fundamental. For the AD7329 defined as where sixth harmonics. ...
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... The AD7329 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 distanced in frequency from the original sine waves, whereas the third-order terms are usually at a frequency close to the input frequencies ...
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... THEORY OF OPERATION CIRCUIT INFORMATION The AD7329 is a fast, 8-channel, 12-bit plus sign, bipolar input, serial ADC. The AD7329 can accept bipolar input ranges that include ±10 V, ±5 V, and ±2 can also accept +10 V unipolar input range. A different analog input range can be programmed on each analog input channel via the on-chip registers ...
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... The analog inputs of the AD7329 can be configured as single- ended, true differential, or pseudo differential via the control register mode bits, as shown in Table 12. The AD7329 can accept true bipolar input signals. On power-up, the analog inputs operate as eight single-ended analog input channels. If true differential or pseudo differential is required, a write to the control register is necessary after power-up to change this configuration ...
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... any extra source impedance on the analog input. The AD7329 enters track mode on the 14 When the AD7329 is run at a throughput rate of 1 MSPS with a 20 MHz SCLK signal, the ADC has approximately 1.5 SCLK periods plus t – input signal ...
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... Figure 35. Typical Connection Diagram, Differential Mode ANALOG INPUT Single-Ended Inputs The AD7329 has a total of eight analog inputs when operating in single-ended mode. Each analog input can be independently programmed to one of the four analog input ranges. In applications where the signal source is high impedance recommended to buffer the signal before applying it to the ADC analog inputs ...
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... and REF ±5V RANGE ±2.5V ±10V 6 RANGE RANGE 4 ±10V RANGE 2 0 ±5V RANGE 2.5V REF ±16. ±12V and REF CC IN AD7329 ±2.5V RANGE /REF = 2.5 V OUT ±2.5V RANGE /REF = 2.5 V OUT ...
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... Figure 43 and Figure 44 show the typical voltage range on the V − pin for various analog input ranges when configured in IN the pseudo differential mode. For example, when the AD7329 is configured to operate in pseudo differential mode and the ±5 V range is selected with 16 −16 and ...
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... AD7329 can handle source impedances kΩ before the THD starts to degrade. Due to the programmable nature of the analog inputs on the AD7329, the choice of op amp used to drive the inputs is a function of the particular application and depends on the input configuration and the analog input voltage ranges selected. ...
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... AD7329 1.5kΩ 2kΩ 1.5kΩ 1.5kΩ 1.5kΩ 1.5kΩ 10kΩ Figure 45. Single-Ended-to-Differential Configuration with the for Bipolar Operation 442Ω 442Ω AD8021 V IN 442Ω 442Ω 442Ω 442Ω AD8021 100Ω Figure 46. Single-Ended-to-Differential Configuration with the V+ V– ...
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... ADDRESSING REGISTERS A serial transfer on the AD7329 consists of 16 SCLK cycles. The three MSBs on the DIN line during the 16 SCLK transfer are decoded to determine which register is addressed. The three MSBs consist of the write bit, Register Select 1 bit, and Register Select 2 bit. The register select bits are used to determine which of the four on-board registers is selected ...
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... The control register is used to select the analog input channel, analog input configuration, reference, coding, and power mode. The control register is a write-only, 12-bit register. Data loaded on the DIN line corresponds to the AD7329 configuration for the next conversion. If the sequence register is being used, data should be loaded into the control register after the range registers and the sequence register have been initialized ...
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... PM1 PM0 Description 1 1 Full shutdown mode. In this mode, all internal circuitry on the AD7329 is powered down. Information in the control register is retained when the AD7329 is in full shutdown mode Autoshutdown mode. The AD7329 enters autoshutdown on the 15 All internal circuitry is powered down in autoshutdown. ...
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... AD7329 SEQUENCE REGISTER The sequence register on the AD7329 is an 8-bit, write-only register. Each of the eight analog input channels has one corresponding bit in the sequence register. To select a channel for inclusion in the sequence, set the corresponding channel bit the sequence register. MSB ...
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... SEQ1 to 0 and SEQ2 to 1. The AD7329 continues to convert the selected sequence without interruption if the sequence register remains unchanged and SEQ1 = 0 and SEQ2 = 1 in the control register. ...
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... To return to traditional multichannel operation, a write to the control register to set SEQ1 to 0 and SEQ2 necessary. When SEQ1 and SEQ2 are both set the AD7329 is configured to operate in traditional multichannel mode, where a write to Channel Address Bit ADD2 to Bit ADD0 in the control register selects the next channel for conversion ...
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... The AD7329 is specified for a 2 reference range. When reference is selected, the ranges are ±12 V, ±6 V, ±3 V, and +12 V. For these ranges, the V must be equal to or greater than the maximum analog input range selected ...
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... Bit PM0, set to 0 (normal mode), the part begins to power the 15 SCLK rising edge when the control register is updated. Figure 53 shows how the AD7329 is configured to exit full shutdown mode. To ensure that the AD7329 is fully powered should elapse before the next CS falling edge. up, t ...
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... The track-and-hold section is in hold mode during autoshutdown. On the rising CS edge, the track-and- hold section, which was in hold during shutdown, returns to track as the AD7329 begins to power up. The time to power up from autoshutdown is 500 μs. When the control register is programmed to transition to autoshutdown mode, it does so on the 15 Figure 54 shows the part entering autoshutdown mode ...
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... AD7329 POWER VS. THROUGHPUT RATE The power consumption of the AD7329 varies with throughput rate. The static power consumed by the AD7329 is very low, and significant power savings can be achieved as the throughput rate is reduced. Figure 55 and Figure 56 show the power vs. throughput rate for the AD7329 and 5 V, respectively ...
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... DOUT line returns to three-state. Depending on where the CS signal is brought high, the addressed register may update. Data is clocked into the AD7329 on the SCLK falling edge. The three MSBs on the DIN line are decoded to select which register is addressed. The control register is a 12-bit register. If the ...
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... AD7329 MICROPROCESSOR INTERFACING The serial interface on the AD7329 allows the part to be directly connected to a range of different microprocessors. This section explains how to interface the AD7329 with some of the most common microcontroller and DSP serial interface protocols. AD7329 TO ADSP-21xx The ADSP-21xx family of DSPs interfaces directly to the AD7329 without requiring glue logic ...
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... All AGND pins on the AD7329 should be connected to the AGND plane. Digital and analog ground pins should be joined in only one place. If the AD7329 system where multiple devices require an AGND and DGND connection, the connection should still be made at only one point ...
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... This board is a complete unit allowing control and communicate with all Analog Devices, Inc., evaluation boards ending in the CB designators. To order a complete evaluation kit, the particular ADC evaluation board (for example, EVAL-AD7329CBZ), the EVAL-CONTROL BRD2Z, and transformer must be ordered. See the relevant evaluation board technical note on for more information. ...
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... NOTES Rev Page AD7329 ...
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... AD7329 NOTES ©2006–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05402-0-2/10(A) Rev Page ...