AD7856–SPECIFICATIONS1, 2 A Grade: fCLKIN = 6 MHz, (–40 ⴗ C to +105 ⴗ C), fSAMPLE = 285 kHz; K Grade:fCLKIN = 4 MHz, (0 ⴗ C to +105 ⴗ C), fSAMPLE = 102 kHz; (AVDD = DVDD = +5.0 V ⴞ 5%,REFIN/REFOUT = 4.096 V External Reference unless otherwise noted, SLEEP = Logic High; TA = TMIN to TMAX, unless otherwise noted.) Specifica- tions apply for Mode 2 operation, standard 3-wire SPI interface; refer to Detailed Timing section for Mode 1 Specifications.ParameterA Version1K Version1UnitsTest Conditions/Comments DYNAMIC PERFORMANCE fIN = 10 kHz Signal to Noise + Distortion Ratio3 (SNR) 78 78 dB min 79.5 dB typ Total Harmonic Distortion (THD) –86 –86 dB max –95 dB typ Peak Harmonic or Spurious Noise –87 –87 dB max –95 dB typ Intermodulation Distortion (IMD) Second Order Terms –86 –90 dB typ fa = 9.983 kHz, fb = 10.05 kHz Third Order Terms –86 –90 dB typ fa = 9.983 kHz, fb = 10.05 kHz Channel-to-Channel Isolation –90 –90 dB typ VIN = 25 kHz DC ACCURACY Any Channel Resolution 14 14 Bits Integral Nonlinearity ±2 LSB max 4.096 V External Reference, VDD = 5 V ±2 LSB typ Differential Nonlinearity ±2 LSB max Guaranteed No Missed Codes to 13 Bits. ±2 LSB typ Offset Error ±10 LSB max ±10 ±5 LSB typ Offset Error Match ±3 LSB max Positive Full-Scale Error ±10 LSB max ±10 LSB typ Positive Full-Scale Error Match ±2 LSB max ANALOG INPUT Input Voltage Ranges 0 to VREF 0 to VREF Volts i.e., AIN(+) – AIN(–) = 0 to VREF, AIN(–) Can Be Biased Up, but AIN(+) Cannot Go Below AIN(–) Leakage Current ±1 ±1 µA max Input Capacitance 20 20 pF typ REFERENCE INPUT/OUTPUT REFIN Input Voltage Range 4.096/VDD 2.3/VDD V min/max Functional from 1.2 V Input Impedance 150 150 kΩ typ Resistor Connected to Internal Reference Node REFOUT Output Voltage 3.696/4.496 3.696/4.496 V min/max REFOUT Tempco 20 20 ppm/°C typ LOGIC INPUTS Input High Voltage, VINH VDD – 1.0 VDD – 1.0 V min Input Low Voltage, VINL 0.4 0.4 V max Input Current, I ± IN 1 ±1 µA max Typically 10 nA, VIN = 0 V or VDD Input Capacitance, C 4 IN 10 10 pF max LOGIC OUTPUTS Output High Voltage, VOH VDD – 0.4 VDD – 0.4 V min ISOURCE = 200 µA Output Low Voltage, VOL 0.4 0.4 V max ISINK = 0.8 mA Floating-State Leakage Current ±1 ±1 µA max Floating-State Output Capacitance4 10 10 pF max Output Coding Straight (Natural) Binary CONVERSION RATE Conversion Time 3.5 5.25 µs max 21 CLKIN Cycles Track/Hold Acquisition Time 0.33 0.5 µs min –2– REV. A