Datasheet AD7719 (Analog Devices) - 5

AD7719 Parameter AD7719B Unit Test Conditions
AUXILIARY CHANNEL (continued) Offset Error3 ±3 µV typ Selected Channel = AIN5/AIN6 Offset Error Drift vs. Temperature4 ±10 nV/°C typ Full-Scale Error6, 7 ±0.75 LSB typ Gain Drift vs. Temperature4 0.5 ppm/°C typ Negative Full-Scale Error ±1 LSB typ Power Supply Rejection (PSR) 70 dB min AIN = 1 V Input Range = ±2.5 V, Typically 80 dB ANALOG INPUTS Differential Input Voltage Ranges ±REFIN2 V nom ARN = 1 ±REFIN2/2 V nom ARN = 0 Absolute AIN Voltage Limits AGND – 30 mV V min Unbuffered Input AVDD + 30 mV V max Analog Input Current 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, SF = 82 @ 60 Hz 100 dB min 60 Hz ±1 Hz, SF = 68 Common-Mode Rejection @ DC 85 dB min Input Range = ±2.5 V, AIN = 1 V @ 50 Hz2 90 dB min 50 Hz ±1 Hz, Range = 2.5 V, AIN = 1 V @ 60 Hz2 90 dB min 60 Hz ±1 Hz, Range = 2.5 V, AIN = 1 V REFERENCE INPUT (REFIN2) With Respect to AGND REFIN2 Voltage 2.5 V nom REFIN2 Range2 1 V min AVDD V max Reference DC Input Current2 0.2 µA/V typ Reference DC Input Current Drift 0.003 nA/V/°C typ EXCITATION CURRENT SOURCES (IEXC1 and IEXC2) Output Current 200 µA nom Initial Tolerance at 25°C ±10 % typ Drift 200 ppm/°C typ Initial Current Matching at 25°C ±1 % typ Matching between IEXC1 and IEXC2 No Load Drift Matching 20 ppm/°C typ Line Regulation (AVDD) 2.1 µA/V max AVDD = 5 V ± 5%. Typically 1.25 µA/V Load Regulation 300 nA/V typ Output Compliance AVDD – 0.6 V max AGND – 30 mV V min LOW-SIDE POWER SWITCHES (SW1, SW2) RON 5 Ω max AVDD = 5 V. Typically 3 Ω 7 Ω max AVDD = 3 V. Typically 4.5 Ω Allowable Current2 20 mA max Continuous Current per Switch TEMPERATURE SENSOR Accuracy See TPC 5 °C typ TRANSDUCER BURNOUT AIN(+) Current –100 nA typ AIN(–) Current 100 nA typ Initial Tolerance @ 25°C ±15 % typ Drift 0.03 %/°C typ SYSTEM CALIBRATION2, 9 Full-Scale Calibration Limit 1.05 × FS10 V max Zero-Scale Calibration Limit –1.05 × FS V min Input Span 0.8 × FS V min 2.1 × FS V max –4– REV. A 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