EVAL-AD7327CB AD [Analog Devices], EVAL-AD7327CB Datasheet
EVAL-AD7327CB
Related parts for EVAL-AD7327CB
EVAL-AD7327CB Summary of contents
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FEATURES 12-bit plus sign SAR ADC True bipolar input ranges Software-selectable input ranges ±10 V, ±5 V, ±2 +10 V 500 kSPS throughput rate Eight analog input channels with channel sequencer Single-ended, true differential, and pseudo ...
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AD7327 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications .................................................................. 7 Absolute Maximum Ratings............................................................ 8 ESD Caution.................................................................................. 8 Pin Configuration and ...
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SPECIFICATIONS 16 − −16 MHz 500 kSPS SCLK S A MAX Table 2. 1 Parameter Min DYNAMIC PERFORMANCE ...
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AD7327 1 Parameter Min 4 DC ACCURACY Resolution 13 No Missing Codes 12-bit plus sign 11-bit plus sign 2 Integral Nonlinearity 2 Differential Nonlinearity 2, 5 Offset Error 2, 5 Offset Error Match 2, 5 Gain Error 2, 5 Gain ...
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Parameter Min ANALOG INPUT Input Voltage Ranges (Programmed via Range Registers) Pseudo Differential V (−) IN Input Range DC Leakage Current Input Capacitance 3 REFERENCE INPUT/OUTPUT Input Voltage Range 2.5 Input DC Leakage Current Input Capacitance Reference Output Voltage ...
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AD7327 1 Parameter Min POWER REQUIREMENTS − 2 2.7 DRIVE Normal Mode (Static) Normal Mode (Operational and I CC DRIVE Autostandby Mode (Dynamic ...
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TIMING SPECIFICATIONS 16 − −16 Timing specifications apply with load, unless otherwise noted. A MAX MIN Table ...
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AD7327 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted A Table 4. Parameter V to AGND, DGND AGND, DGND AGND, DGND AGND, DGND DRIVE AGND ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 5. Pin Function Descriptions Pin No. Mnemonic Description 1 CS Chip Select. Active low logic input. This input provides the dual function of initiating conversions on the AD7327 and frames the serial data transfer. ...
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AD7327 TYPICAL PERFORMANCE CHARACTERISTICS 0 4096 POINT FFT V CC – 25°C A INT/EXT 2.5V REFERENCE –40 ±10V RANGE F = 50kHz IN SNR = 77.30dB –60 SINAD = 76.85dB THD = –86.96dB SFDR ...
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DRIVE ±12V – 25° 500kSPS – +10V SE INTERNAL REFERENCE –65 ±10V SE –70 – +10V DIFF –80 ...
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AD7327 8k 7600 1201 1165 –3 –2 –1 0 CODE Figure 16. Histogram of Codes, Single-Ended Mode –50 –55 –60 –65 – –75 – ...
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DRIVE ±12V – 25°C A INTERNAL REF –60 RANGE = ±10V AND ±2. 500kSPS –65 S SINGLE-ENDED MODE –70 –75 –80 –85 –90 –95 ...
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AD7327 TERMINOLOGY Differential Nonlinearity This is the difference between the measured and the ideal 1 LSB change between any two adjacent codes in the ADC. Integral Nonlinearity This is the maximum deviation from a straight line passing through the endpoints ...
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Channel-to-Channel Isolation Channel-to-channel isolation is a measure of the level of crosstalk between any two channels measured by applying a full-scale, 100 kHz sine wave signal to all unselected input channels and determining the degree to which the ...
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AD7327 THEORY OF OPERATION CIRCUIT INFORMATION The AD7327 is a fast, 8-channel, 12-bit plus sign, bipolar input, serial A/D converter. The AD7327 can accept bipolar input ranges that include ±10 V, ±5 V, and ±2 can also accept ...
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COMPARATOR SW1 SW2 AGND Figure 24. ADC Conversion Phase (Single-Ended) Figure 25 shows the differential configuration during the acquisition phase. For the conversion phase, SW3 opens and SW1 and SW2 move to Position ...
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AD7327 – Figure 30. Equivalent Analog Input Circuit (Differential) Care should be taken to ensure that the analog input does not ...
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TYPICAL CONNECTION DIAGRAM Figure 32 shows a typical connection diagram for the AD7327. In this configuration, the AGND pin is connected to the analog ground plane of the system, and the DGND pin is connected to the digital ground plane ...
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AD7327 5 ±5V RANGE 4 3 ±2.5V RANGE ±10V –1 RANGE –2 ±10V RANGE –3 – – REF –6 ±16. ±12V Figure 35. Common-Mode Range ...
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RANGE ±5V RANGE ±2.5V 6 RANGE ±10V 4 RANGE 2 0 –2 ±10V RANGE – +10V –6 RANGE 2.5V REF –8 ±16. ±12V Figure 40. ...
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AD7327 REGISTERS The AD7327 has four programmable registers: the control register, sequence register, Range Register 1, and Range Register 2. These registers are write-only registers. ADDRESSING REGISTERS A serial transfer on the AD7327 consists of 16 SCLK cycles. The three ...
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CONTROL REGISTER 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 AD7327 configuration ...
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AD7327 Table 11. Power Mode Selection PM1 PM0 Description 1 1 Full Shutdown Mode. In this mode, all internal circuitry on the AD7327 is powered down. Information in the control register is retained when the AD7327 is in full shutdown ...
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SEQUENCE REGISTER The sequence register on the AD7327 is an 8-bit, write-only register. Each of the eight analog input channels has one corresponding bit in the sequence register. To select an analog input channel for inclusion in the sequence, set ...
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AD7327 SEQUENCER OPERATION CS DIN: WRITE TO CONTROL REGISTER TO STOP THE SEQUENCE, Seq1 = 0, Seq2 = 0. DOUT: CONVERSION RESULT FROM CHANNEL IN SEQUENCE. The AD7327 can be configured to automatically cycle through a number of selected channels ...
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If a change to one of the range registers is required during a sequence necessary to first stop the sequence by writing to the control register and setting Seq1 to 0 and Seq2 to 0. Next, the write ...
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AD7327 REFERENCE The AD7327 can operate with either the internal 2.5 V on-chip reference or an externally applied reference. The internal reference is selected by setting the Ref bit in the control register power-up, the Ref bit ...
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MODES OF OPERATION The AD7327 has several modes of operation that are designed to provide flexible power management options. These options can be chosen to optimize the power dissipation/throughput rate ratio for different application requirements. The mode of operation of ...
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AD7327 AUTOSHUTDOWN MODE (PM1 = 1, PM0 = 0) Once the autoshutdown mode is selected, the AD7327 auto- th matically enters shutdown on the 15 SCLK rising edge. In autoshutdown mode, all internal circuitry is powered down. The AD7327 retains ...
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POWER VS. THROUGHPUT RATE The power consumption of the AD7327 varies with throughput rate. The static power consumed by the AD7327 is very low, and significant power savings can be achieved as the throughput rate is reduced. Figure 51 and ...
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AD7327 SERIAL INTERFACE Figure 53 shows the timing diagram for the serial interface of the AD7327. The serial clock applied to the SCLK pin provides the conversion clock and controls the transfer of information to and from the AD7327 during ...
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MICROPROCESSOR INTERFACING The serial interface on the AD7327 allows the part to be directly connected to a range of different microprocessors. This section explains how to interface the AD7327 with some common microcontroller and DSP serial interface protocols. AD7327 TO ...
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AD7327 APPLICATION HINTS LAYOUT AND GROUNDING The printed circuit board that houses the AD7327 should be designed so that the analog and digital sections are confined to certain areas of the board. This design facilitates the use of ground planes ...
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... This board is a complete unit allowing control and communicate with all Analog Devices evaluation boards ending in the CB designators. To order a complete evaluation kit, the particular ADC evaluation board (for example, EVAL-AD7327CB), the EVAL-CONTROL BRD2, and transformer must be ordered. See the relevant evaluation board technical note for more information ...
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AD7327 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05401–0–1/06(0) Rev Page ...