AD7273/AD7274PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONSVDD 18AGNDVDD 18VINAD7273/AD7273/SDATA27CSSDATA27DGNDAD7274AD7274DGND36SCLKCS36SCLKTOP VIEWTOP VIEW(Not to Scale)AGNDVV4(Not to Scale)5V45REFINREF 04973-008 04973-009 Figure 8. 8-Lead MSOP Pin Configuration Figure 9. 8-Lead TSOT Pin Configuration Table 6. Pin Function DescriptionsPin No.MSOP TSOT Mnemonic Description 1 1 VDD Power Supply Input. The VDD range for the AD7273/AD7274 is from 2.35 V to 3.6 V. 2 2 SDATA Data Out. Logic output. The conversion result from the AD7273/AD7274 is provided on this output as a serial data stream. The bits are clocked out on the falling edge of the SCLK input. The data stream from the AD7274 consists of two leading zeros followed by the 12 bits of conversion data and two trailing zeros, provided MSB first. The data stream from the AD7273 consists of two leading zeros followed by the 10 bits of conversion data and four trailing zeros, provided MSB first. 3 7 CS Chip Select. Active low logic input. This input provides the dual function of initiating conversion on the AD7273/AD7274 and framing the serial data transfer. 4 8 AGND Analog Ground. Ground reference point for all circuitry on the AD7273/AD7274. All analog signals and any external reference signal should be referred to this AGND voltage. 5 5 VREF Voltage Reference Input. This pin becomes the reference voltage input. An external reference should be applied at this pin. The external reference input range is 1.4 V to VDD. A 10 μF capacitor should be tied between this pin and AGND. 6 6 SCLK Serial Clock. Logic input. SCLK provides the serial clock for accessing data from the part. This clock input is also used as the clock source for the conversion process of AD7273/AD7274. 7 3 DGND Digital Ground. Ground reference point for all digital circuitry on the AD7273/AD7274. The DGND and AGND voltages ideally should be at the same potential and must not be more than 0.3 V apart, even on a transient basis. 8 4 VIN Analog Input. Single-ended analog input channel. The input range is 0 to VREF. Rev. 0 | Page 10 of 28 Document Outline FEATURES GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS REVISION HISTORY SPECIFICATIONS AD7274 SPECIFICATIONS AD7273 SPECIFICATIONS TIMING SPECIFICATIONS TIMING EXAMPLES Timing Example 1 Timing Example 2 ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TERMINOLOGY CIRCUIT INFORMATION CONVERTER OPERATION ADC TRANSFER FUNCTION TYPICAL CONNECTION DIAGRAM ANALOG INPUT DIGITAL INPUTS MODES OF OPERATION NORMAL MODE PARTIAL POWER-DOWN MODE FULL POWER-DOWN MODE POWER-UP TIMES POWER VS. THROUGHPUT RATE SERIAL INTERFACE MICROPROCESSOR INTERFACING AD7273/AD7274 to ADSP-BF53x APPLICATION HINTS GROUNDING AND LAYOUT EVALUATING THE AD7273/AD7274 PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE