Datasheet AD7770 (Analog Devices) - 9

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AD7770 Data Sheet Parameter Test Conditions/Comments Min Typ Max Unit
Offset Matching 25 µV Gain Error ±0.1 % FS Gain Drift vs. Temperature ±0.75 ppm/°C Gain Matching ±0.1 % SAR ADC Speed and Performance Resolution 12 Bits Analog Input Range AVSS4 + 0.1 AVDD4 − 0.1 V Analog Input Common-Mode AVSS4 + 0.1 (AVDD4 + AVDD4 − 0.1 V Range AVSS4)/2 Analog Input Dynamic Current 256 kSPS, 0 dBFS ±100 nA Throughput 256 kSPS DC Accuracy Differential mode INL 1.5 LSB DNL No missing codes (12-bit) −0.99 +1 LSB Offset ±1 LSB Gain 12 LSB AC Performance SNR 1 kHz 66 dB THD 1 kHz −81 dB VCM PIN Output (AVDD1x + V AVSSx)/2 Load Current, IL 1 mA Load Regulation, ∆VOUT/∆IL 12 mV/mA Short-Circuit Current 5 mA LOGIC INPUTS Input Voltage High, VIH 0.7 × IOVDD V Low, VIL 0.4 V Hysteresis 0.1 V Input Currents −10 +10 µA LOGIC OUTPUTS3 Output Voltage High, VOH IOVDD ≥ 3 V, ISOURCE = 1 mA 0.8 × IOVDD V 2.3 V ≤ IOVDD < 3 V, ISOURCE = 0.8 × IOVDD V 500 μA IOVDD < 2.3 V, ISOURCE = 200 μA 0.8 × IOVDD V Low, VOL IOVDD ≥ 3 V, ISINK = 2 mA 0.4 V 2.3 V ≤ IOVDD < 3 V, ISINK = 1 mA 0.4 V IOVDD < 2.3 V, ISINK = 100 μA 0.4 V Leakage Current Floating state −10 +10 µA Output Capacitance Floating state 10 pF Σ-Δ ADC Data Output Coding Twos complement SAR ADC Data Output Coding Binary Rev. C | Page 8 of 97 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION REVISION HISTORY FUNCTIONAL BLOCK DIAGRAM SPECIFICATIONS DOUTx TIMING CHARACTERISTISTICS SPI TIMING CHARACTERISTISTICS SYNCHRONIZATION PINS AND RESET TIMING CHARACTERISTICS SAR ADC TIMING CHARACTERISTISTICS GPIO SRC UPDATE TIMING CHARACTERISTISTICS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION ANALOG INPUTS TRANSFER FUNCTION CORE SIGNAL CHAIN CAPACITIVE PGA INTERNAL REFERENCE AND REFERENCE BUFFERS INTEGRATED LDOs CLOCKING AND SAMPLING DIGITAL RESET AND SYNCHRONIZATION PINS DIGITAL FILTERING SHUTDOWN MODE CONTROLLING THE AD7770 PIN CONTROL MODE SPI CONTROL Functionality Available in SPI Mode Offset and Gain Correction SPI Control Functionality Global Control Functions Per Channel Functions Phase Adjustment PGA Gain Decimation GPIOx Pins Σ-Δ Reference Configuration Power Modes LDO Bypassing DIGITAL SPI SPI CRC—Checksum Protection (SPI Control Mode) SPI Read/Write Register Mode (SPI Control Mode) SPI SAR Diagnostic Mode (SPI Control Mode) Σ-Δ Data, ADC Mode SPI Software Reset RMS NOISE AND RESOLUTION HIGH RESOLUTION MODE LOW POWER MODE DIAGNOSTICS AND MONITORING SELF DIAGNOSTICS ERROR General Errors MCLK Switch Error (SPI Control Mode) Reset Detection Internal LDO Status ROM and Memory Map CRC Σ-Δ ADC Errors Reference Detect (SPI Control Mode) Overvoltage and Undervoltage Events Modulator Saturation Filter Saturation Output Saturation SPI Transmission Errors (SPI Control Mode) CRC Checksum Error SCLK Counter Invalid Read Invalid Write MONITORING USING THE AD7770 SAR ADC(SPI CONTROL MODE) Temperature Sensor Σ-Δ ADC DIAGNOSTICS (SPI CONTROL MODE) (-∆ OUTPUT DATA ADC CONVERSION OUTPUT—HEADER AND DATA CRC Header ERROR Header (SPI Control Mode) SRC (SPI CONTROL MODE) SRC Bandwidth SRC Group Delay and Latency Settling Time DATA OUTPUT INTERFACE DOUT3 to DOUT0 Data Interface Standalone Mode Daisy-Chain Mode Minimum DCLKx Frequency SPI CALCULATING THE CRC CHECKSUM Σ-Δ CRC Checksum SPI Control Mode Checksum REGISTER SUMMARY REGISTER DETAILS CHANNEL 0 CONFIGURATION REGISTER CHANNEL 1 CONFIGURATION REGISTER CHANNEL 2 CONFIGURATION REGISTER CHANNEL 3 CONFIGURATION REGISTER CHANNEL 4 CONFIGURATION REGISTER CHANNEL 5 CONFIGURATION REGISTER CHANNEL 6 CONFIGURATION REGISTER CHANNEL 7 CONFIGURATION REGISTER DISABLE CLOCKS TO ADC CHANNEL REGISTER CHANNEL 0 SYNC OFFSET REGISTER CHANNEL 1 SYNC OFFSET REGISTER CHANNEL 2 SYNC OFFSET REGISTER CHANNEL 3 SYNC OFFSET REGISTER CHANNEL 4 SYNC OFFSET REGISTER CHANNEL 5 SYNC OFFSET REGISTER CHANNEL 6 SYNC OFFSET REGISTER CHANNEL 7 SYNC OFFSET REGISTER GENERAL USER CONFIGURATION 1 REGISTER GENERAL USER CONFIGURATION 2 REGISTER GENERAL USER CONFIGURATION 3 REGISTER DATA OUTPUT FORMAT REGISTER MAIN ADC METER AND REFERENCE MUX CONTROL REGISTER GLOBAL DIAGNOSTICS MUX REGISTER GPIO CONFIGURATION REGISTER GPIO DATA REGISTER BUFFER CONFIGURATION 1 REGISTER BUFFER CONFIGURATION 2 REGISTER CHANNEL 0 OFFSET UPPER BYTE REGISTER CHANNEL 0 OFFSET MIDDLE BYTE REGISTER CHANNEL 0 OFFSET LOWER BYTE REGISTER CHANNEL 0 GAIN UPPER BYTE REGISTER CHANNEL 0 GAIN MIDDLE BYTE REGISTER CHANNEL 0 GAIN LOWER BYTE REGISTER CHANNEL 1 OFFSET UPPER BYTE REGISTER CHANNEL 1 OFFSET MIDDLE BYTE REGISTER CHANNEL 1 OFFSET LOWER BYTE REGISTER CHANNEL 1 GAIN UPPER BYTE REGISTER CHANNEL 1 GAIN MIDDLE BYTE REGISTER CHANNEL 1 GAIN LOWER BYTE REGISTER CHANNEL 2 OFFSET UPPER BYTE REGISTER CHANNEL 2 OFFSET MIDDLE BYTE REGISTER CHANNEL 2 OFFSET LOWER BYTE REGISTER CHANNEL 2 GAIN UPPER BYTE REGISTER CHANNEL 2 GAIN MIDDLE BYTE REGISTER CHANNEL 2 GAIN LOWER BYTE REGISTER CHANNEL 3 OFFSET UPPER BYTE REGISTER CHANNEL 3 OFFSET MIDDLE BYTE REGISTER CHANNEL 3 OFFSET LOWER BYTE REGISTER CHANNEL 3 GAIN UPPER BYTE REGISTER CHANNEL 3 GAIN MIDDLE BYTE REGISTER CHANNEL 3 GAIN LOWER BYTE REGISTER CHANNEL 4 OFFSET UPPER BYTE REGISTER CHANNEL 4 OFFSET MIDDLE BYTE REGISTER CHANNEL 4 OFFSET LOWER BYTE REGISTER CHANNEL 4 GAIN UPPER BYTE REGISTER CHANNEL 4 GAIN MIDDLE BYTE REGISTER CHANNEL 4 GAIN LOWER BYTE REGISTER CHANNEL 5 OFFSET UPPER BYTE REGISTER CHANNEL 5 OFFSET MIDDLE BYTE REGISTER CHANNEL 5 OFFSET LOWER BYTE REGISTER CHANNEL 5 GAIN UPPER BYTE REGISTER CHANNEL 5 GAIN MIDDLE BYTE REGISTER CHANNEL 5 GAIN LOWER BYTE REGISTER CHANNEL 6 OFFSET UPPER BYTE REGISTER CHANNEL 6 OFFSET MIDDLE BYTE REGISTER CHANNEL 6 OFFSET LOWER BYTE REGISTER CHANNEL 6 GAIN UPPER BYTE REGISTER CHANNEL 6 GAIN MIDDLE BYTE REGISTER CHANNEL 6 GAIN LOWER BYTE REGISTER CHANNEL 7 OFFSET UPPER BYTE REGISTER CHANNEL 7 OFFSET MIDDLE BYTE REGISTER CHANNEL 7 OFFSET LOWER BYTE REGISTER CHANNEL 7 GAIN UPPER BYTE REGISTER CHANNEL 7 GAIN MIDDLE BYTE REGISTER CHANNEL 7 GAIN LOWER BYTE REGISTER CHANNEL 0 STATUS REGISTER CHANNEL 1 STATUS REGISTER CHANNEL 2 STATUS REGISTER CHANNEL 3 STATUS REGISTER CHANNEL 4 STATUS REGISTER CHANNEL 5 STATUS REGISTER CHANNEL 6 STATUS REGISTER CHANNEL 7 STATUS REGISTER CHANNEL 0/CHANNEL 1 DSP ERRORS REGISTER CHANNEL 2/CHANNEL 3 DSP ERRORS REGISTER CHANNEL 4/CHANNEL 5 DSP ERRORS REGISTER CHANNEL 6/CHANNEL 7 DSP ERRORS REGISTER CHANNEL 0 TO CHANNEL 7 ERROR REGISTER ENABLE REGISTER GENERAL ERRORS REGISTER 1 GENERAL ERRORS REGISTER 1 ENABLE GENERAL ERRORS REGISTER 2 GENERAL ERRORS REGISTER 2 ENABLE ERROR STATUS REGISTER 1 ERROR STATUS REGISTER 2 ERROR STATUS REGISTER 3 DECIMATION RATE (N) MSB REGISTER DECIMATION RATE (N) LSB REGISTER DECIMATION RATE (IF) MSB REGISTER DECIMATION RATE (IF) LSB REGISTER SRC LOAD SOURCE AND LOAD UPDATE REGISTER OUTLINE DIMENSIONS ORDERING GUIDE