Datasheet AD7719 (Analog Devices) - 4

AD7719–SPECIFICATIONS1(AVDD = 2.7 V to 3.6 V or 4.75 V to 5.25 V, DVDD = 2.7 V to 3.6 V or 4.75 V to 5.25 V, REFIN(+) = 2.5 V; REFIN(–) = AGND; AGND = DGND = 0 V; XTAL1/XTAL2 = 32.768 kHz Crystal; all specifications TMIN to TMAX, unless otherwise noted.) Parameter AD7719B Unit Test Conditions
ADC CHANNEL SPECIFICATION Output Update Rate 5.4 Hz min Both Channels Synchronized 105 Hz max 0.732 ms Increments MAIN CHANNEL No Missing Codes2 24 Bits min 20 Hz Update Rate Resolution 13 Bits p-p ±20 mV Range, 20 Hz Update Rate 18 Bits p-p ±2.56 V Range, 20 Hz Update Rate Output Noise and Update Rates See Tables II to V 2 1 024 . REFIN1 Integral Nonlinearity ±10 ppm of FSR max Typically 2 ppm. FSR = × Offset Error3 ±3 µV typ Gain Offset Error Drift vs. Temperature4 ±10 nV/°C typ Full-Scale Error5, 6, 7 ±10 µV typ At the Calibrated Conditions Gain Drift vs. Temperature4 ±0.5 ppm/°C typ Power Supply Rejection (PSR) 80 dB min Input Range = ±2.56 V, 100 dB typ. 110 dB typ on ±20 mV Range ANALOG INPUTS Differential Input Voltage Ranges ±1.024 × REFIN1/GAIN V nom REFIN1 = REFIN1(+) – REFIN1(–) GAIN = 1 to 128. ADC Range Matching ±2 µV typ Input Voltage = 19 mV on All Ranges Absolute AIN Voltage Limits AGND + 100 mV V min BUF = 0; Buffered Mode of Operation AVDD – 100 mV V max Analog Input Current2 BUF = 0 DC Input Current ±1 nA max DC Input Current Drift ±5 pA /°C typ Absolute AIN Voltage Limits AGND – 30 mV V min BUF = 1; Unbuffered mode of operation. AVDD + 30 mV V max Analog Input Current BUF = 1. Unbuffered Mode of Operation. DC Input Current ±125 nA/V typ Input Current Varies with Input Voltage DC Input Current Drift ±2 pA/V/°C typ Normal-Mode Rejection2, 8 @ 50 Hz 100 dB min 50 Hz ± 1 Hz, 16.65 Hz Update Rate, SF = 82 @ 60 Hz 100 dB min 60 Hz ± 1 Hz, 20 Hz Update Rate, SF = 68 Common-Mode Rejection @ DC 90 dB min Input Range = ±2.56 V, AIN = 1 V. 100 dB typ. 110 dB typ on ±20 mV Range @ 50 Hz2 100 dB min 50 Hz ± 1 Hz, Range = ±2.56 V, AIN = 1 V @ 60 Hz2 100 dB min 60 Hz ± 1 Hz, Range = ±2.56 V, AIN = 1 V REFERENCE INPUT (REFIN1) REFIN1 Voltage 2.5 V nom REFIN1 = REFIN1(+) – REFIN1(–) REFIN1 Voltage Range2 1 V min AVDD V max REFIN1 Common-Mode Range AGND – 30 mV V min AVDD + 30 mV V max Reference DC Input Current 0.5 µA/V typ Reference DC Input Current Drift ±0.01 nA/V/°C typ Normal-Mode Rejection2, 8 @ 50 Hz 100 dB min 50 Hz ± 1 Hz, SF = 82 @ 60 Hz 100 dB min 60 Hz ± 1 Hz, SF = 68 Common-Mode Rejection @ DC 110 dB typ Input Range = ±2.56 V, AIN = 1 V @ 50 Hz 110 dB typ 50 Hz ± 1 Hz, Range = 2.56 V, AIN = 1 V @ 60 Hz 110 dB typ 60 Hz ± 1 Hz, Range = 2.56 V, AIN = 1 V Reference Detect Levels 0.3 V min NOXREF Bit Active if VREF < 0.3 V 0.65 V max NOXREF Bit Inactive if VREF > 0.65 V AUXILIARY CHANNEL No Missing Codes2 16 Bits min Resolution 16 Bits p-p ±2.5 V Range, 20 Hz Update Rate Output Noise and Update Rates See Tables VI and VIII Integral Nonlinearity ±15 ppm of FSR max REV. A –3– Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ORDERING GUIDE TIMING CHARACTERISTICS DIGITAL INTERFACE PIN CONFIGURATION PIN FUNCTION DESCRIPTIONS Typical Performance Characteristics DUAL-CHANNEL ADC CIRCUIT INFORMATION Overview Main Channel Auxiliary Channel Both Channels MAIN AND AUXILIARY ADC NOISE PERFORMANCE ON-CHIP REGISTERS Communications Register (A3, A2, A1, A0 = 0, 0, 2, 0) Status Register (A3, A2, A1, A0 = 0, 0, 0, 0; Power-On Reset = 0x00) Mode Register (A3, A2, A1, A0 = 0, 0, 0, 1; Power-On Reset = 0x00) Operating Characteristics when Addressing the Mode and Control Registers Main ADC Control Register (AD0CON): (A3, A2, A1, A0 = 0, 0, 1, 0; Power-On Reset = 0x07) Aux ADC Control Registers (AD1CON): (A3, A2, A1, A0 = 0, 0, 1, 1; Power-On Reset = 0x00) Filter Register (A3, A2, A1, A0 = 0, 1, 0, 0; Power-On Reset = 0x45) I/O and Current Source Control Register (IOCON): (A3, A2, A1, A0 = 0, 1, 1, 1; Power-On Reset = 0x0000) Main ADC Data Result Registers (DATA0): (A3, A2, A1, A0 = 0, 1, 0, 1; Power-On Reset = 0x00 0000) Aux ADC Data Result Registers (DATA1): (A3, A2, A1, A0 = 0, 1, 1, 0; Power-On Reset = 0x0000) Main ADC Offset Calibration Coefficient Registers (OF0): (A3, A2, A1, A0 = 1, 0, 0, 0; Power-On Reset = 0x80 0000) Aux ADC Offset Calibration Coefficient Registers (OF1): (A3, A2, A1, A0 = 1, 0, 0, 1; Power-On Reset = 0x8000) Main ADC Gain Calibration Coefficient Registers (GNO): (A3, A2, A1, A0 = 1, 0, 1, 0; Power-On Reset = 0x5X XXX5) Aux ADC Gain Calibration Coefficient Registers (GN1): (A3, A2, A1, A0 = 1, 0, 1, 1; Power-On Reset = 0x59XX) ID Register (ID): (A3, A2, A1, A0 = 1, 1, 1, 1; Power-On Reset = 0x0X) User Nonprogrammable Test Registers CONFIGURING THE AD7719 MICROCOMPUTER/MICROPROCESSOR INTERFACING AD7719-to-68HC11 Interface AD7719-to-8xC51 Interface AD7719-to-ADSP-2103/ADSP-2105 Interface CIRCUIT DESCRIPTION Analog Input Channels Programmable Gain Amplifier Bipolar/Unipolar Configuration Data Output Coding Burnout Currents Excitation Currents Crystal Oscillator Reference Input Reference Detect Reset Input Power-Down Mode Idle Mode ADC Disable Mode Calibration Grounding and Layout APPLICATIONS Pressure Measurement Temperature Measurement 3-Wire RTD Configurations Smart Transmitters OUTLINE DIMENSIONS Revision History