Datasheet AD7766 (Analog Devices) - 10

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AD7766 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS AV 1 DD 16 CS V 2 REF+ 15 SDI AD7766/ REFGND 3 14 MCLK AD766-1/ V 4 IN+ 13 AD7766-2 SCLK V 5 TOP VIEW IN– 12 DRDY (Not to Scale) AGND 6 11 DGND SYNC/PD 7 10 SDO
6 00
DV 8 9 V
9-
DD DRIVE
44 06 Figure 6. 16-Lead TSSOP Pin Configuration
Table 5. Pin Function Descriptions Pin No. Mnemonic Description
1 AVDD +2.5 V Analog Power Supply. 2 VREF+ Reference Input for the AD7766/AD7766-1/AD7766-2. An external reference must be applied to this input pin. The VREF+ input can range from 2.4 V to 5 V. The reference voltage input is independent of the voltage magnitude applied to the AVDD pin. 3 REFGND Reference Ground. Ground connection for the reference voltage. The input reference voltage (VREF+) should be decoupled to this pin. 4 VIN+ Positive Input of the Differential Analog Input. 5 VIN− Negative Input of the Differential Analog Input. 6 AGND Power Supply Ground for Analog Circuitry. 7 SYNC/PD Synchronization and Power-Down Input Pin. This pin has dual functionality. It can be used to synchronize multiple AD7766/AD7766-1/AD7766-2 devices and/or to put the AD7766/AD7766-1/AD7766-2 devices into power-down mode. See the Power-Down, Reset, and Synchronization section for further details. 8 DVDD 2.5 V Digital Power Supply Input. In cases where a logic voltage of 2.5 V for interfacing is used, (2.5 V applied to VDRIVE pin), the DVDD and VDRIVE pins may be connected to the same voltage supply rail. 9 VDRIVE Logic Power Supply Input, 1.8 V to 3.6 V. The voltage supplied at this pin determines the operating voltage of the digital logic interface. 10 SDO Serial Data Output. The conversion result from the AD7766/AD7766-1/AD7766-2 is output on the SDO pin as a 24-bit, twos complement, MSB first, serial data stream. 11 DGND Digital Logic Power Supply Ground. 12 DRDY Data Ready Output. A falling edge on the DRDY signal indicates that a new conversion data result is available in the output register of the AD7766/AD7766-1/AD7766-2. See the AD7766/AD7766-1/AD77662-2 Interface section for further details. 13 SCLK Serial Clock Input. The SCLK input provides the serial clock for all serial data transfers with the AD7766/AD7766-1/ AD7766-2 devices. See the AD7766/AD7766-1/AD77662-2 Interface section for further details. 14 MCLK Master Clock Input. The sampling frequency of the AD7766/AD7766-1/AD7766-2 is equal to the MCLK frequency. 15 SDI Serial Data Input. This is the daisy-chain input of the AD7766/AD7766-1/AD7766-2. See the Daisy Chaining section for further details. 16 CS Chip Select Input. The CS input selects a specific AD7766/AD7766-1/AD7766-2 device and acts as an enable on the SDO pin. In cases where CS is used, the MSB of the conversion result is clocked onto the SDO line on the CS falling edge. The CS input allows multiple AD7766/AD7766-1/AD7766-2 devices to share the same SDO line. This allows the user to select the appropriate device by supplying it with a logic low CS signal, which enables the SDO pin of the device concerned. See the AD7766/AD7766-1/AD77662-2 Interface section for further details. Rev. C | Page 9 of 24 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION RELATED DEVICES TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION AD7766/AD7766-1/AD7766-2 TRANSFER FUNCTION CONVERTER OPERATION ANALOG INPUT STRUCTURE SUPPLY AND REFERENCE VOLTAGES AD7766/AD7766-1/AD77662-2 INTERFACE INITIAL POWER-UP READING DATA POWER-DOWN, RESET, AND SYNCHRONIZATION DAISY CHAINING READING DATA IN DAISY-CHAIN MODE CHOOSING THE SCLK FREQUENCY DAISY-CHAIN MODE CONFIGURATION AND TIMING DIAGRAMS DRIVING THE AD7766/AD7766-1/AD7766-2 DIFFERENTIAL SIGNAL SOURCE SINGLE-ENDED SIGNAL SOURCE ANTIALIASING POWER DISSIPATION VREF+ INPUT SIGNAL MULTIPLEXING ANALOG INPUT CHANNELS OUTLINE DIMENSIONS ORDERING GUIDE