Datasheet AD7785 (Analog Devices) - 3
| Hersteller | Analog Devices |
| Beschreibung | 3-Channel, Low Noise, Low Power, 20-Bit Σ-Δ ADC with On-Chip In-Amp and Reference |
| Seiten / Seite | 33 / 3 — AD7785. TABLE OF CONTENTS. REVISION HISTORY. 4/07—Revision 0: Initial … |
| Dateiformat / Größe | PDF / 485 Kb |
| Dokumentensprache | Englisch |
AD7785. TABLE OF CONTENTS. REVISION HISTORY. 4/07—Revision 0: Initial Version
Modelllinie für dieses Datenblatt
Textversion des Dokuments
link to page 1 link to page 1 link to page 1 link to page 1 link to page 1 link to page 1 link to page 1 link to page 1 link to page 3 link to page 3 link to page 4 link to page 4 link to page 7 link to page 7 link to page 8 link to page 8 link to page 9 link to page 9 link to page 9 link to page 9 link to page 10 link to page 10 link to page 12 link to page 12 link to page 12 link to page 12 link to page 13 link to page 13 link to page 14 link to page 14 link to page 15 link to page 15 link to page 15 link to page 15 link to page 16 link to page 16 link to page 16 link to page 16 link to page 18 link to page 18 link to page 19 link to page 19 link to page 19 link to page 19 link to page 19 link to page 19 link to page 20 link to page 20 link to page 20 link to page 20 link to page 21 link to page 21 link to page 21 link to page 21 link to page 22 link to page 22 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 26 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 27 link to page 28 link to page 28 link to page 28 link to page 28 link to page 28 link to page 28 link to page 28 link to page 28 link to page 30 link to page 30 link to page 30 link to page 30 link to page 31 link to page 31 link to page 32 link to page 32 link to page 32 link to page 32
AD7785 TABLE OF CONTENTS
Features .. 1 Offset Register .. 19 Applications... 1 Full-Scale Register.. 19 General Description ... 1 ADC Circuit Information.. 20 Functional Block Diagram .. 1 Overview ... 20 Revision History ... 2 Digital Interface.. 21 Specifications... 3 Circuit Description... 25 Timing Characteristics... 6 Analog Input Channel ... 25 Timing Diagrams.. 7 Instrumentation Amplifier.. 25 Absolute Maximum Ratings.. 8 Bipolar/Unipolar Configuration .. 25 ESD Caution.. 8 Data Output Coding .. 25 Pin Configuration and Function Descriptions... 9 Burnout Currents ... 26 Output Noise and Resolution Specifications .. 11 Excitation Currents .. 26 External Reference.. 11 Bias Voltage Generator .. 26 Internal Reference .. 12 Reference ... 26 Typical Performance Characteristics ... 13 Reset ... 26 On-Chip Registers .. 14 AVDD Monitor ... 27 Communications Register... 14 Calibration... 27 Status Register ... 15 Grounding and Layout .. 27 Mode Register ... 15 Applications Information .. 29 Configuration Register .. 17 Temperature Measurement using a Thermocouple... 29 Data Register ... 18 Temperature Measurement using an RTD.. 30 ID Register... 18 Outline Dimensions ... 31 IO Register... 18 Ordering Guide .. 31
REVISION HISTORY 4/07—Revision 0: Initial Version
Rev. 0 | Page 2 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING CHARACTERISTICS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS OUTPUT NOISE AND RESOLUTION SPECIFICATIONS EXTERNAL REFERENCE INTERNAL REFERENCE TYPICAL PERFORMANCE CHARACTERISTICS ON-CHIP REGISTERS COMMUNICATIONS REGISTER RS2, RS1, RS0 = 0, 0, 0 STATUS REGISTER RS2, RS1, RS0 = 0, 0, 0; Power-On/Reset = 0x88 MODE REGISTER RS2, RS1, RS0 = 0, 0, 1; Power-On/Reset = 0x000A CONFIGURATION REGISTER RS2, RS1, RS0 = 0, 1, 0; Power-On/Reset = 0x0710 DATA REGISTER RS2, RS1, RS0 = 0, 1, 1; Power-On/Reset = 0x00000F ID REGISTER RS2, RS1, RS0 = 1, 0, 0; Power-On/Reset = 0xXB IO REGISTER RS2, RS1, RS0 = 1, 0, 1; Power-On/Reset = 0x00 OFFSET REGISTER RS2, RS1, RS0 = 1, 1, 0; Power-On/Reset = 0x800000 FULL-SCALE REGISTER RS2, RS1, RS0 = 1, 1, 1; Power-On/Reset = 0x5XXX00 ADC CIRCUIT INFORMATION OVERVIEW DIGITAL INTERFACE Single Conversion Mode Continuous Conversion Mode Continuous Read CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL INSTRUMENTATION AMPLIFIER BIPOLAR/UNIPOLAR CONFIGURATION DATA OUTPUT CODING BURNOUT CURRENTS EXCITATION CURRENTS BIAS VOLTAGE GENERATOR REFERENCE RESET AVDD MONITOR CALIBRATION GROUNDING AND LAYOUT APPLICATIONS INFORMATION TEMPERATURE MEASUREMENT USING A THERMOCOUPLE TEMPERATURE MEASUREMENT USING AN RTD OUTLINE DIMENSIONS ORDERING GUIDE
AD7785 TABLE OF CONTENTS
Features .. 1 Offset Register .. 19 Applications... 1 Full-Scale Register.. 19 General Description ... 1 ADC Circuit Information.. 20 Functional Block Diagram .. 1 Overview ... 20 Revision History ... 2 Digital Interface.. 21 Specifications... 3 Circuit Description... 25 Timing Characteristics... 6 Analog Input Channel ... 25 Timing Diagrams.. 7 Instrumentation Amplifier.. 25 Absolute Maximum Ratings.. 8 Bipolar/Unipolar Configuration .. 25 ESD Caution.. 8 Data Output Coding .. 25 Pin Configuration and Function Descriptions... 9 Burnout Currents ... 26 Output Noise and Resolution Specifications .. 11 Excitation Currents .. 26 External Reference.. 11 Bias Voltage Generator .. 26 Internal Reference .. 12 Reference ... 26 Typical Performance Characteristics ... 13 Reset ... 26 On-Chip Registers .. 14 AVDD Monitor ... 27 Communications Register... 14 Calibration... 27 Status Register ... 15 Grounding and Layout .. 27 Mode Register ... 15 Applications Information .. 29 Configuration Register .. 17 Temperature Measurement using a Thermocouple... 29 Data Register ... 18 Temperature Measurement using an RTD.. 30 ID Register... 18 Outline Dimensions ... 31 IO Register... 18 Ordering Guide .. 31
REVISION HISTORY 4/07—Revision 0: Initial Version
Rev. 0 | Page 2 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING CHARACTERISTICS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS OUTPUT NOISE AND RESOLUTION SPECIFICATIONS EXTERNAL REFERENCE INTERNAL REFERENCE TYPICAL PERFORMANCE CHARACTERISTICS ON-CHIP REGISTERS COMMUNICATIONS REGISTER RS2, RS1, RS0 = 0, 0, 0 STATUS REGISTER RS2, RS1, RS0 = 0, 0, 0; Power-On/Reset = 0x88 MODE REGISTER RS2, RS1, RS0 = 0, 0, 1; Power-On/Reset = 0x000A CONFIGURATION REGISTER RS2, RS1, RS0 = 0, 1, 0; Power-On/Reset = 0x0710 DATA REGISTER RS2, RS1, RS0 = 0, 1, 1; Power-On/Reset = 0x00000F ID REGISTER RS2, RS1, RS0 = 1, 0, 0; Power-On/Reset = 0xXB IO REGISTER RS2, RS1, RS0 = 1, 0, 1; Power-On/Reset = 0x00 OFFSET REGISTER RS2, RS1, RS0 = 1, 1, 0; Power-On/Reset = 0x800000 FULL-SCALE REGISTER RS2, RS1, RS0 = 1, 1, 1; Power-On/Reset = 0x5XXX00 ADC CIRCUIT INFORMATION OVERVIEW DIGITAL INTERFACE Single Conversion Mode Continuous Conversion Mode Continuous Read CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL INSTRUMENTATION AMPLIFIER BIPOLAR/UNIPOLAR CONFIGURATION DATA OUTPUT CODING BURNOUT CURRENTS EXCITATION CURRENTS BIAS VOLTAGE GENERATOR REFERENCE RESET AVDD MONITOR CALIBRATION GROUNDING AND LAYOUT APPLICATIONS INFORMATION TEMPERATURE MEASUREMENT USING A THERMOCOUPLE TEMPERATURE MEASUREMENT USING AN RTD OUTLINE DIMENSIONS ORDERING GUIDE