link to page 15 link to page 9 link to page 4 link to page 4 link to page 4 link to page 4 link to page 4 Data SheetAD7688SPECIFICATIONS VDD = 4.5 V to 5.5 V, VIO = 2.3 V to VDD, VREF = VDD, TA = –40°C to +85°C, unless otherwise noted. Table 2. ParameterConditionsMinTypMaxUnit RESOLUTION 16 Bits ANALOG INPUT Voltage Range IN+ − IN− −VREF +VREF V Absolute Input Voltage IN+, IN− −0.1 VREF + 0.1 V Common-Mode Input Range IN+, IN− 0 VREF/2 VREF/2 + 0.1 V Analog Input CMRR fIN = 250 kHz 65 dB Leakage Current at 25°C Acquisition phase 1 nA Input Impedance See the Analog Input section ACCURACY No Missing Codes 16 Bits Differential Linearity Error −1 ±0.4 +1 LSB1 Integral Linearity Error −1.5 ±0.4 +1.5 LSB Transition Noise REF = VDD = 5 V 0.4 LSB Gain Error2, TMIN to TMAX ±2 ±6 LSB Gain Error Temperature Drift ±0.3 ppm/°C Zero Error2, TMIN to TMAX ±0.1 ±1.6 mV Zero Temperature Drift ±0.3 ppm/°C Power Supply Sensitivity VDD = 5 V ± 5% ±0.05 LSB THROUGHPUT Conversion Rate 0 500 kSPS Transient Response Full-scale step 400 ns AC ACCURACY Dynamic Range VREF = 5 V 95.8 96.5 dB3 Signal-to-Noise fIN = 20 kHz, VREF = 5 V 94 95.5 dB fIN = 20 kHz, VREF = 5 V 92.5 dB Spurious-Free Dynamic Range fIN = 20 kHz −118 dB Total Harmonic Distortion fIN = 20 kHz −118 dB Signal-to-(Noise + Distortion) fIN = 20 kHz, VREF = 5 V 93.5 95 dB fIN = 20 kHz, VREF = 5 V, −60 dB input 36.5 dB Intermodulation Distortion4 115 dB 1 LSB means least significant bit. With the ±5 V input range, one LSB is 152.6 µV. 2 See the Terminology section. These specifications do include full temperature range variation but do not include the error contribution from the external reference. 3All specifications in dB are referred to a full-scale input FS. Tested with an input signal at 0.5 dB below full-scale, unless otherwise specified. 4 fIN1 = 21.4 kHz, fIN2 = 18.9 kHz, each tone at −7 dB below full-scale. Rev. B | Page 3 of 28 Document Outline Features Applications Application Diagram General Description Table of Contents Revision History Specifications Timing Specifications Absolute Maximum Ratings Thermal Resistance ESD Caution Pin Configuration and Function Descriptions Terminology Typical Performance Characteristics Circuit Information Converter Operation Transfer Functions Typical Connection Diagram Analog Input Driver Amplifier Choice Single-to-Differential Driver Voltage Reference Input Power Supply Supplying the ADC from the Reference Digital Interface /CS Mode 3-Wire, No BUSY Indicator /CS Mode 3-Wire with BUSY Indicator /CS Mode 4-Write, No BUSY Indicator /CS Mode 4-Wire with BUSY Indicator Chain Mode, No BUSY Indicator Chain Mode with BUSY Indicator Application Hints Layout Evaluating the AD7688 Performance Outline Dimensions Ordering Guide