link to page 33 link to page 5 link to page 5 link to page 5 link to page 33 link to page 5 link to page 5 link to page 5 link to page 5 link to page 5 link to page 5 link to page 5 link to page 5 link to page 20 AD7631Data SheetParameter Conditions/CommentsMinTypMaxUnit INTERNAL REFERENCE PDREF = PDBUF = low Output Voltage REF @ 25°C 4.965 5.000 5.035 V Temperature Drift –40°C to +85°C ±3 ppm/°C Line Regulation AVDD = 5 V ± 5% ±15 ppm/V Long-Term Drift 1000 hours 50 ppm Turn-On Settling Time CREF = 22 μF 10 ms REFERENCE BUFFER PDREF = high REFBUFIN Input Voltage Range 2.4 2.5 2.6 V EXTERNAL REFERENCE PDREF = PDBUF = high Voltage Range REF 4.75 5 AVDD + 0.1 V Current Drain 250 kSPS throughput 250 μA TEMPERATURE PIN Voltage Output @ 25°C 311 mV Temperature Sensitivity 1 mV/°C Output Resistance 4.33 kΩ DIGITAL INPUTS Logic Levels VIL −0.3 +0.6 V VIH 2.1 OVDD + 0.3 V IIL −1 +1 μA IIH −1 +1 μA DIGITAL OUTPUTS Data Format Parallel or serial 18-bit Pipeline Delay5 VOL ISINK = 500 μA 0.4 V VOH ISOURCE = −500 μA OVDD − 0.6 V POWER SUPPLIES Specified Performance AVDD 4.756 5 5.25 V DVDD 4.75 5 5.25 V OVDD 2.7 5.25 V VCC 7 15 15.75 V VEE −15.75 −15 0 V Operating Current7 @ 250 kSPS throughput AVDD With Internal Reference8 8.5 mA With Internal Reference Disabled8 6.1 mA DVDD 4 mA OVDD 0.1 mA VCC VCC = 15 V, with internal reference buffer 1.4 mA VCC = 15 V 0.8 mA VEE VEE = −15 V 0.7 mA Power Dissipation @ 250 kSPS throughput With Internal Reference8 94 120 mW With Internal Reference Disabled8 73 100 mW In Power-Down Mode9 PD = high 10 μW TEMPERATURE RANGE10 Specified Performance TMIN to TMAX −40 +85 °C 1 In all input ranges, the input current scales with throughput. See the Analog Inputs section. 2 Linearity is tested using endpoints, not best fit. All linearity is tested with an external 5 V reference. 3 LSB means least significant bit. All specifications in LSB do not include the error contributed by the reference. 4 All specifications in decibels are referred to a full-scale range input, FSR. Tested with an input signal at 0.5 dB below full-scale, unless otherwise specified. 5 Conversion results are available immediately after completed conversion. 6 4.75 V or VREF − 0.1 V, whichever is larger. 7 Tested in parallel reading mode. 8 With internal reference, PDREF = PDBUF = low; with internal reference disabled, PDREF = PDBUF = high. With internal reference buffer, PDBUF = low. 9 With all digital inputs forced to OVDD. 10 Consult sales for extended temperature range. Rev. B | Page 4 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY THEORY OF OPERATION OVERVIEW CONVERTER OPERATION TRANSFER FUNCTIONS TYPICAL CONNECTION DIAGRAM ANALOG INPUTS Input Range Selection Input Structure Single-to-Differential Driver VOLTAGE REFERENCE INPUT/OUTPUT Internal Reference (REF = 5 V)(PDREF = Low, PDBUF = Low) External 2.5 V Reference and Internal Buffer (REF = 5 V)(PDREF = High, PDBUF = Low) External 5 V Reference (PDREF = High, PDBUF = High) Reference Decoupling Temperature Sensor POWER SUPPLIES Core Supplies High Voltage Supplies Digital Output Supply Power Sequencing Power Dissipation vs. Throughput Power Down CONVERSION CONTROL INTERFACES DIGITAL INTERFACE RESET PARALLEL INTERFACE Master Parallel Interface Slave Parallel Interface 18-Bit Interface (Master or Slave) 16-Bit and 8-Bit Interface (Master or Slave) SERIAL INTERFACE Data Interface Serial Configuration Interface MASTER SERIAL INTERFACE Internal Clock (MODE[1:0] = 3, EXT/ = Low) Read During Convert (RDC = High) Read After Convert (RDC = Low, DIVSCLK[1:0] = [0 to 3]) SLAVE SERIAL INTERFACE External Clock (MODE[1:0] = 3, EXT/ = High) External Discontinuous Clock Data Read After Conversion Daisy-Chain Feature External Clock Data Read During Previous Conversion External Clock Data Read After/During Conversion HARDWARE CONFIGURATION SOFTWARE CONFIGURATION MICROPROCESSOR INTERFACING SPI Interface APPLICATION INFORMATION LAYOUT GUIDELINES EVALUATING PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE