Datasheet AD7891 (Analog Devices) - 3

AD7891–SPECIFICATIONS (VDD = 5 V
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5%, AGND = DGND = 0 V, REF IN = 2.5 V. All specifications TMIN to TMAX, unless otherwise noted.) Parameter A Version1 B Version Y Version Unit Test Conditions/Comments
DYNAMIC PERFORMANCE2 Sample Rate = 454.5 kSPS3 (AD7891-1), 500 kSPS3 (AD7891-2). Any channel. Signal-to-(Noise + Distortion) Ratio4 @ 25∞C 70 70 70 dB min TMIN to TMAX 70 70 70 dB min Total Harmonic Distortion4 –78 –78 –78 dB max Peak Harmonic or Spurious Noise4 –80 –80 –80 dB max Intermodulation Distortion4 fa = 9 kHz, fb = 9.5 kHz. Second-Order Terms –80 –80 –80 dB typ Third-Order Terms –80 –80 –80 dB typ Channel-to-Channel Isolation4 –80 –80 –80 dB max DC ACCURACY Any channel. Resolution 12 12 12 Bits Minimum Resolution for which No Missing Codes Are Guaranteed 12 12 12 Bits Relative Accuracy4 ±1 ±0.75 ±1 LSB max Differential Nonlinearity4 ±1 ±1 ±1 LSB max Positive Full-Scale Error4 ±3 ±3 ±3 LSB max Positive Full-Scale Error Match4, 5 0.6 0.6 0.6 LSB typ 1.5 LSB max. Unipolar Offset Error ±4 ±4 ±4 LSB max Input ranges of 0 V to 2.5 V, 0 V to 5 V. Unipolar Offset Error Match5 0.1 0.1 0.1 LSB typ 1 LSB max. Negative Full-Scale Error4 ±3 ±3 ±3 LSB max Input ranges of ± 2.5 V, ± 5 V, ± 10 V. Negative Full-Scale Error Match4, 5 0.6 0.6 0.6 LSB typ 1.5 LSB max. Bipolar Zero Error ±4 ±4 ±4 LSB max Input ranges of ± 2.5 V, ± 5 V, ± 10 V. Bipolar Zero Error Match5 0.2 0.2 0.2 LSB typ 1.5 LSB max. ANALOG INPUTS AD7891-1 Input Voltage Range ±5 ±5 ±5 V Input applied to both VINXA and VINXB. ±10 ±10 ±10 V Input applied to VINXA, VINXB = AGND. AD7891-1 VINXA Input Resistance 7.5 7.5 7.5 kW min Input range of ± 5 V. AD7891-1 VINXA Input Resistance 15 15 15 kW min Input range of ± 10 V. AD7891-2 Input Voltage Range 0 to 2.5 0 to 2.5 0 to 2.5 V Input applied to both VINXA and VINXB. 0 to 5 0 to 5 0 to 5 V Input applied to VINXA, VINXB = AGND. ±2.5 ±2.5 ±2.5 V Input applied to VINXA, VINXB = REF IN6. AD7891-2 VINXA Input Resistance 1.5 1.5 1.5 kW min Input ranges of ± 2.5 V and 0 V to 5 V. AD7891-2 VINXA Input Current ±50 ±50 ±50 nA max Input range of 0 V to 2.5 V. REFERENCE INPUT/OUTPUT REF IN Input Voltage Range 2.375/2.625 2.375/2.625 2.375/2.625 V min/V max 2.5 V ± 5%. Input Impedance 1.6 1.6 1.6 kW min Resistor connected to internal reference node. Input Capacitance5 10 10 10 pF max REF OUT Output Voltage 2.5 2.5 2.5 V nom REF OUT Error @ 25∞C ±10 ±10 ±10 mV max T ± MIN to TMAX 20 ±20 ±20 mV max REF OUT Temperature Coefficient 25 25 25 ppm/∞C typ REF OUT Output Impedance 5 5 5 kW nom See REF IN input impedance. LOGIC INPUTS Input High Voltage, VINH 2.4 2.4 2.4 V min VDD = 5 V ± 5%. Input Low Voltage, VINL 0.8 0.8 0.8 V max VDD = 5 V ± 5%. Input Current, I ± INH 10 ±10 ±10 mA max Input Capacitance5 CIN 10 10 10 pF max –2– REV. D Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS TIMING CHARACTERISTICS ORDERING GUIDE PIN CONFIGURATIONS PIN FUNCTION DESCRIPTIONS PARALLEL INTERFACE MODE FUNCTIONS Data I/O Lines Parallel Read Operation SERIAL INTERFACE MODE FUNCTIONS CONTROL REGISTER TERMINOLOGY Signal-to-(Noise + Distortion) Ratio Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise Intermodulation Distortion Channel-to-Channel Isolation Relative Accuracy Differential Nonlinearity Positive Full-Scale Error (AD7891-1, ±10 V and ±5 V; AD7891-2, ±2.5 V) Positive Full-Scale Error (AD7891-2, 0 V to 5 V and 0 V to 2.5 V) Bipolar Zero Error (AD7891-1, ±10 V and ±5 V; AD7891-2, ±2.5 V) Unipolar Offset Error (AD7891-2, 0 V to 5 V and 0 V to 2.5 V) Negative Full-Scale Error (AD7891-1, ±10 V and ±5V; AD7891-2, ±2.5 V) Track/Hold Acquisition Time CONVERTER DETAILS INTERFACE INFORMATION Parallel Interface Mode Serial Interface Mode Simplifying the Serial Interface CIRCUIT DESCRIPTION Reference Analog Input Section Track/Hold Amplifier STANDBY Operation MICROPROCESSOR INTERFACING AD7891 to 8X51 Serial Interface AD7891 to 68HC11 Serial Interface AD7891 to ADSP-21xx Serial Interface AD7891 to DSP5600x Serial Interface AD7891 to TMS320xxx Serial Interface PARALLEL INTERFACING AD7891 to ADSP-21xx AD7891 to TMS32020, TMS320C25, and TMS320C5x AD7891 to TMS320C3x AD7891 to DSP5600x Power Supply Bypassing and Grounding AD7891 PERFORMANCE Linearity Noise Dynamic Performance Effective Number of Bits OUTLINE DIMENSIONS Revision History