Datasheet AD7124-4 (Analog Devices) - 6

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Data Sheet AD7124-4 SPECIFICATIONS
AVDD = 2.9 V to 3.6 V (full power mode), 2.7 V to 3.6 V (mid and low power mode), IOVDD = 1.65 V to 3.6 V, AVSS = DGND = 0 V, REFINx(+) = 2.5 V, REFINx(−) = AVSS, master clock = 614.4 kHz, all specifications TMIN to TMAX, unless otherwise noted.
Table 2. Parameter1 Min Typ Max Unit Test Conditions/Comments
ADC Output Data Rate, fADC Low Power Mode 1.17 2400 SPS Mid Power Mode 2.34 4800 SPS Full Power Mode 9.38 19,200 SPS No Missing Codes2 24 Bits FS3 > 2, sinc4 filter 24 Bits FS3 > 8, sinc3 filter Resolution See the RMS Noise and Resolution section RMS Noise and Update Rates See the RMS Noise and Resolution section Integral Nonlinearity (INL) −4 ±1 +4 ppm of FSR Gain = 12 −15 ±2 +15 ppm of FSR Gain > 14 Offset Error5 Before Calibration ±15 µV Gain = 1 to 8 200/gain µV Gain = 16 to 128 After Internal Calibration/System In order of Calibration noise Offset Error Drift vs. Temperature6 Low Power Mode 10 nV/°C Gain = 1 or gain > 16 80 nV/°C Gain = 2 to 8 40 nV/°C Gain = 16 Mid Power Mode 10 nV/°C Gain = 1 or gain > 16 40 nV/°C Gain = 2 to 8 20 nV/°C Gain = 16 Full Power Mode 10 nV/°C Gain Error5, 7 Before Internal Calibration −0.0025 +0.0025 % Gain = 1, TA = 25°C −0.3 % Gain > 1 After Internal Calibration −0.016 +0.004 +0.016 % Gain = 2 to 8, TA = 25°C ±0.025 % Gain = 16 to 128 After System Calibration In order of noise Gain Error Drift vs. Temperature 1 2 ppm/°C Power Supply Rejection AIN = 1 V/gain, external reference Low Power Mode 87 dB Gain = 2 to 16 96 dB Gain = 1 or gain > 16 Mid Power Mode2 92 dB Gain = 2 to 16 100 dB Gain = 1 or gain > 16 Full Power Mode 99 dB Common-Mode Rejection8 At DC2 85 90 dB AIN = 1 V, gain = 1 105 115 dB AIN = 1 V/gain, gain 2 or 4 1029, 2 dB AIN = 1 V/gain, gain 2 or 4 115 120 dB AIN = 1 V/gain, gain ≥ 8 1059, 2 dB AIN = 1 V/gain, gain ≥ 8 Sinc3, Sinc4 Filter2 At 50 Hz, 60 Hz 120 dB 10 SPS, 50 Hz ± 1 Hz, 60 Hz ± 1 Hz At 50 Hz 120 dB 50 SPS, 50 Hz ± 1 Hz At 60 Hz 120 dB 60 SPS, 60 Hz ± 1 Hz Rev. C | Page 5 of 91 Document Outline FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY GENERAL DESCRIPTION SPECIFICATIONS TIMING CHARACTERISTICS Timing Diagrams ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY RMS NOISE AND RESOLUTION FULL POWER MODE Sinc4 Sinc3 Post Filters Fast Settling Filter (Sinc4 + Sinc1) Fast Settling Filter (Sinc3 + Sinc1) MID POWER MODE Sinc4 Sinc3 Post Filters Fast Settling Filter (Sinc4 + Sinc1) Fast Settling Filter (Sinc3 + Sinc1) LOW POWER MODE Sinc4 Sinc3 Post Filters Fast Settling Filter (Sinc4 + Sinc1) Fast Settling Filter (Sinc3 + Sinc1) GETTING STARTED OVERVIEW Power Modes Analog Inputs Multiplexer Reference Programmable Gain Array (PGA) Burnout Currents Σ-Δ ADC and Filter Channel Sequencer Per Channel Configuration Serial Interface Clock Temperature Sensor Digital Outputs Calibration Excitation Currents Bias Voltage Bridge Power Switch (PSW) Diagnostics POWER SUPPLIES Single Supply Operation (AVSS = DGND) Split Supply Operation (AVSS ≠ DGND) DIGITAL COMMUNICATION Accessing the ADC Register Map CONFIGURATION OVERVIEW Channel Configuration Channel Registers ADC Setups Configuration Registers Filter Registers Offset Registers Gain Registers Diagnostics ADC Control Register Understanding Configuration Flexibility ADC CIRCUIT INFORMATION ANALOG INPUT CHANNEL EXTERNAL IMPEDANCE WHEN USING A GAIN OF 1 PROGRAMMABLE GAIN ARRAY (PGA) REFERENCE BIPOLAR/UNIPOLAR CONFIGURATION DATA OUTPUT CODING EXCITATION CURRENTS BRIDGE POWER-DOWN SWITCH LOGIC OUTPUTS BIAS VOLTAGE GENERATOR CLOCK POWER MODES STANDBY AND POWER-DOWN MODES DIGITAL INTERFACE Single Conversion Mode Continuous Conversion Mode Continuous Read Mode DATA_STATUS SERIAL INTERFACE RESET (DOUT__DEL AND _EN BITS) RESET CALIBRATION SPAN AND OFFSET LIMITS SYSTEM SYNCHRONIZATION DIGITAL FILTER SINC4 FILTER Sinc4 Output Data Rate/Settling Time Sinc4 Zero Latency Sequencer Sinc4 50 Hz and 60 Hz Rejection SINC3 FILTER Sinc3 Output Data Rate and Settling Time Sinc3 Zero Latency Sequencer Sinc3 50 Hz and 60 Hz Rejection FAST SETTLING MODE (SINC4 + SINC1 FILTER) Output Data Rate and Settling Time, Sinc4 + Sinc1 Filter Sequencer 50 Hz and 60 Hz Rejection, Sinc4 + Sinc1 Filter FAST SETTLING MODE (SINC3 + SINC1 FILTER) Output Data Rate and Settling Time, Sinc3 + Sinc1 Filter Sequencer 50 Hz and 60 Hz Rejection, Sinc3 + Sinc1 Filter POST FILTERS SUMMARY OF FILTER OPTIONS DIAGNOSTICS SIGNAL CHAIN CHECK REFERENCE DETECT CALIBRATION, CONVERSION, AND SATURATION ERRORS OVERVOLTAGE/UNDERVOLTAGE DETECTION POWER SUPPLY MONITORS LDO MONITORING Power Supply Monitor LDO Capacitor Detect MCLK COUNTER SPI SCLK COUNTER SPI READ/WRITE ERRORS SPI_IGNORE ERROR CHECKSUM PROTECTION MEMORY MAP CHECKSUM PROTECTION ROM CHECKSUM PROTECTION CRC Calculation Example of a Polynomial CRC Calculation—24-Bit Word: 0x654321 (8-Bit Command and 16-Bit Data) BURNOUT CURRENTS TEMPERATURE SENSOR GROUNDING AND LAYOUT APPLICATIONS INFORMATION TEMPERATURE MEASUREMENT USING A THERMOCOUPLE TEMPERATURE MEASUREMENT USING AN RTD FLOWMETER ON-CHIP REGISTERS COMMUNICATIONS REGISTER STATUS REGISTER ADC_CONTROL REGISTER DATA REGISTER IO_CONTROL_1 REGISTER IO_CONTROL_2 REGISTER ID REGISTER ERROR REGISTER ERROR_EN REGISTER MCLK_COUNT REGISTER CHANNEL REGISTERS CONFIGURATION REGISTERS FILTER REGISTERS OFFSET REGISTERS GAIN REGISTERS OUTLINE DIMENSIONS ORDERING GUIDE