Datasheet AD7322 (Analog Devices)

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2-Channel, Software-Selectable, True Bipolar Input, 1 MSPS, 12-Bit Plus Sign ADC Data Sheet AD7322 FEATURES FUNCTIONAL BLOCK DIAGRAM 12-bit plus sign SAR ADC VDD REFIN/OUT VCC True bipolar input ranges AD7322 Software-selectable input ranges ±10 V, ±5 V, ±2.5 V, 0 V to +10 V 2.5V 1 MSPS throughput rate VREF VIN0 13-BIT I/P SUCCESSIVE Two analog input channels with channel sequencer MUX T/H V APPROXIMATION IN1 ADC Single-ended, true differential, and pseudo differential analog input capability High analog input impedance Low power: 21 mW DOUT Full power signal bandwidth: 22 MHz CHANNEL CONTROL LOGIC SCLK SEQUENCER AND REGISTERS CS Internal 2.5 V reference DIN High speed serial interface Power-down modes VDRIVE
001
14-lead TSSOP package AGND VSS DGND
04863-
i CMOS process technology
Figure 1.
GENERAL DESCRIPTION PRODUCT HIGHLIGHTS
The AD73221 is a 2-channel, 12-bit plus sign, successive approx- 1. The AD7322 can accept true bipolar analog input signals, imation analog-to-digital converter (ADC) designed on the ±10 V, ±5 V, and ±2.5 V, and 0 V to +10 V unipolar signals. iCMOS™ (industrial CMOS) process. iCMOS is a process 2. The two analog inputs can be configured as two single- combining high voltage silicon with submicron CMOS and ended inputs, one true differential input, or one pseudo complementary bipolar technologies. It enables the develop- differential input. ment of a wide range of high performance analog ICs capable of 3. 1 MSPS serial interface. SPI-/QSPI™-/DSP-/MICROWIRE™- 33 V operation in a footprint that no previous generation of high compatible interface. voltage parts could achieve. Unlike analog ICs using conventional 4. Low power, 31 mW maximum, at 1 MSPS throughput rate. CMOS processes, iCMOS components can accept bipolar input 5. Channel sequencer. signals while providing increased performance, dramatically reduced power consumption, and reduced package size.
Table 1. Similar Devices
The AD7322 can accept true bipolar analog input signals. The
Device Throughput Number of
AD7322 has four software-selectable input ranges, ±10 V, ±5 V,
Number Rate Number of bits Channels
±2.5 V, and 0 V to +10 V. Each analog input channel can be AD7329 1000 kSPS 12-bit plus sign 8 independently programmed to one of the four input ranges. AD7328 1000 kSPS 12-bit plus sign 8 The analog input channels on the AD7322 can be programmed AD7327 500 kSPS 12-bit plus sign 8 to be single-ended, true differential, or pseudo differential. AD7324 1000 kSPS 12-bit plus sign 4 AD7323 500 kSPS 12-bit plus sign 4 The ADC contains a 2.5 V internal reference. The AD7322 also AD7321 500 kSPS 12-bit plus sign 2 allows for external reference operation. If a 3 V reference is applied to the REFIN/OUT pin, the AD7322 can accept a true bipolar ±12 V analog input. Minimum ±12 V VDD and VSS supplies are required for the ±12 V input range. The ADC has a high speed serial interface that can operate at throughput rates up to 1 MSPS. 1 Protected by U.S. Patent No. 6,731,232.
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Document Outline Features Functional Block Diagram General Description Table of Contents Revision History Specifications Timing Specifications Absolute Maximum Ratings ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Terminology Theory of Operation Circuit Information Converter Operation Output Coding Transfer Functions Analog Input Structure Track-and-Hold Section Typical Connection Diagram Analog Input Single-Ended Inputs True Differential Mode Pseudo Differential Inputs Driver Amplifier Choice Registers Addressing Registers Control Register Range Register Sequencer Operation Reference VDRIVE Modes of Operation Normal Mode (PM1 = PM0 = 0) Full Shutdown Mode (PM1 = PM0 = 1) Autoshutdown Mode (PM1 = 1, PM0 = 0) Autostandby Mode (PM1 = 0, PM0 = 1) Power vs. Throughput Rate Serial Interface Microprocessor Interfacing AD7322 to ADSP-21xx AD7322 to ADSP-BF53x Application Hints Layout and Grounding Power Supply Configuration Outline Dimensions Ordering Guide