Datasheet AD7732 (Analog Devices) - 7

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AD7732 TIMING SPECIFICATIONS Table 2. (AVDD = 5 V ± 5%; DVDD = 2.7 V to 3.6 V, or 5 V ± 5%; Input Logic 0 = 0 V; Logic 1 = DVDD; unless otherwise noted.)1 Parameter Min Typ Max Unit Test Conditions/Comments
Master Clock Range 1 6.144 MHz t1 50 ns SYNC Pulsewidth t2 500 ns RESET Pulsewidth Read Operation t4 0 ns CS Falling Edge to SCLK Falling Edge Setup Time t 2 5 SCLK Falling Edge to Data Valid Delay 0 60 ns DVDD of 4.75 V to 5.25 V 0 80 ns DVDD of 2.7 V to 3.3 V t 2, 3 5A CS Falling Edge to Data Valid Delay 0 60 ns DVDD of 4.75 V to 5.25 V 0 80 ns DVDD of 2.7 V to 3.3 V t6 50 ns SCLK High Pulsewidth t7 50 ns SCLK Low Pulsewidth t8 0 ns CS Rising Edge after SCLK Rising Edge Hold Time t 4 9 10 80 ns Bus Relinquish Time after SCLK Rising Edge Write Operation t11 0 ns CS Falling Edge to SCLK Falling Edge Setup t12 30 ns Data Valid to SCLK Rising Edge Setup Time t13 25 ns Data Valid after SCLK Rising Edge Hold Time t14 50 ns SCLK High Pulsewidth t15 50 ns SCLK Low Pulsewidth t16 0 ns CS Rising Edge after SCLK Rising Edge Hold Time 1 Sample tested during initial release to ensure compliance. All input signals are specified with tr = tf = 5 ns (10% to 90% of DVDD) and timed from a voltage level of 1.6 V. See Figure 2 and Figure 3. 2 These numbers are measured with the load circuit of Figure 4 and defined as the time required for the output to cross the VOL or VOH limits. 3 This specification is relevant only if CS goes low while SCLK is low. 4 These numbers are derived from the measured time taken by the data output to change 0.5 V when loaded with the circuit of Figure 4. The measured number is then extrapolated back to remove effects of charging or discharging the 50 pF capacitor. This means that the times quoted in the Timing Characteristics are the true bus relinquish times of the part and as such are independent of external bus loading capacitances. Rev. A | Page 6 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM REVISION HISTORY AD7732—SPECIFICATIONS Table 1. (–40°C to +105°C; AVDD = 5 V ± 5%; DVDD = 2.7 V to 3.6 V, or 5 V ± 5%; BIAS (all), REFIN(+) = 2.5 V; REFIN(–) = AGND; RA, RB, RC, RD open circuit; AIN Range = ±10 V; fMCLKIN = 6.144 MHz; unless otherwise noted.) TIMING SPECIFICATIONS Table 2. (AVDD = 5 V ± 5%; DVDD = 2.7 V to 3.6 V, or 5 V ± 5%; Input Logic 0 = 0 V; Logic 1 = DVDD; unless otherwise noted.) ABSOLUTE MAXIMUM RATINGS Table 3. TA = 25°C, unless otherwise noted. TYPICAL PERFORMANCE CHARACTERISTICS OUTPUT NOISE AND RESOLUTION SPECIFICATION Chopping Enabled Table 4. Typical Output RMS Noise in µV vs. Conversion Time and Input Range with Chopping Enabled Table 5. Typical Effective Resolution in Bits vs. Conversion Time and Input Range with Chopping Enabled Table 6. Typical Peak-to-Peak Resolution in Bits vs. Conversion Time and Input Range with Chopping Enabled Chopping Disabled Table 7. Typical Output RMS Noise in µV vs. Conversion Time and Input Range with Chopping Disabled Table 8. Typical Effective Resolution in Bits vs. Conversion Time and Input Range with Chopping Disabled Table 9. Typical Peak-to-Peak Resolution in Bits vs. Conversion Time and Input Range with Chopping Disabled PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS Table 10. Pin Function Descriptions—28-Lead TSSOP REGISTER DESCRIPTION Table 11. Register Summary Table 12. Operational Mode Summary Table 13. Input Range Summary Register Access Communications Register Table 14. I/O Port Register Revision Register Test Register ADC Status Register Checksum Register ADC Zero-Scale Calibration Register ADC Full-Scale Register Channel Data Registers Channel Zero-Scale Calibration Registers Channel Full-Scale Calibration Registers Channel Status Registers Channel Setup Registers Table 15. Channel Conversion Time Registers Mode Register DIGITAL INTERFACE DESCRIPTION Hardware Reset Access the AD7732 Registers Single Conversion and Reading Data Dump Mode Continuous Conversion Mode Continuous Read (Continuous Conversion) Mode CIRCUIT DESCRIPTION Analog Front End Analog Input’s Extended Voltage Range Table 16. Extended Input Voltage Range, Nominal Voltage Range ±10 V, 16 Bits, CLAMP = 0 Table 17. Extended Input Voltage Range, Nominal Voltage Range 0 V to +10 V, 16 Bits, CLAMP = 0 Chopping Multiplexer, Conversion, and Data Output Timing Sigma-Delta ADC Frequency Response Voltage Reference Inputs Reference Detect I/O Port Calibration ADC Zero-Scale Self-Calibration Per Channel System Calibration High Common-Mode Voltage Application OUTLINE DIMENSIONS Ordering Guide