AD974 Data Sheet - Analog Devices

1 REV. AInformation furnished by Analog Devices is believed to be accurate andreliable. However, no responsibility is assumed by Analog Devices for itsuse, nor for any infringements of patents or other rights of third partieswhich may result from its use. No license is granted by implication orotherwise under any patent or patent rights of Analog Technology Way, Box 9106, Norwood, MA 02062-9106, : 781/329-4700 World Wide Web Site: : 781/326-8703 Analog Devices , Inc., 19994-Channel, 16-Bit, 200 kSPSData Acquisition SystemFUNCTIONAL BLOCK DIAGRAMCONTROL LOGIC&CALIBRATION CIRCUITRYPWRDV1AV1 BBIPCAPREFVDIGVANAEXT/ TO 1 MUX+LATCHENV2AV2BV3AV3BV4AV4 BSWITCHEDCAP ADCSERIALINTERFACE16 DATARESISTIVENETWORKRESISTIVENETWORKRESI STIVENETWORKRESISTIVENETWORKCLOCKFEATURE SFast 16-Bit ADC with 200 kSPS ThroughputFour Single-Ended Analog Input ChannelsSingle +5 V Supply OperationInput Ranges.

2 0 V to +4 V, 0 V to +5 V and 610 V120 mW Max Power DissipationPower-Down Mode 50 mWChoice of External or Internal V ReferenceOn-Chip ClockPower-Down ModeGENERAL DESCRIPTIONThe AD974 is a four-channel, data acquisition system with aserial interface. The part contains an input multiplexer, a high-speed 16-bit sampling ADC and a + V reference. All of thisoperates from a single +5 V power supply that also has a power-down mode. The part will accommodate 0 V to +4 V, 0 V to+5 V or 10 V Analog input interface is designed for an efficient transfer of data whilerequiring a low number of AD974 is comprehensively tested for ac parameters such asSNR and THD, as well as the more traditional parameters ofoffset, gain and AD974 is fabricated on Analog Devices BiCMOS process,which has high performance bipolar Devices along with AD974 is available in 28-lead DIP, SOIC and HIGHLIGHTS1.

3 The AD974 is a complete data acquisition system combininga four-channel multiplexer, a 16-bit sampling ADC and a+ V reference on a single The part operates from a single +5 V supply and also has apower-down Interfacing to the AD974 is simple with a low number ofinterconnect The AD974 is comprehensively specified for ac parameterssuch as SNR and THD, as well as dc parameters such aslinearity and offset and gain A 2 AD974 SPECIFICATIONS A Grade B GradeParameterConditionsMinTypMaxMin TypMaxUnitsRESOLUTION1616 BitsANALOG INPUTV oltage Range 10 V, 0 V to +4 V, 0 V to +5 V (See Table I)ImpedanceChannel On or Off (See Table I)Sampling Capacitance4040pFTHROUGHPUT SPEEDC omplete Cycle(Acquire and Convert)55 sThroughput Rate200200kHzDC ACCURACYI ntegral Linearity Error 3 Linearity Error 2+3 1+ Missing Codes1516 BitsTransition Error3 Internal Reference Error DriftInternal Reference 7 7ppm/ CFull-Scale ErrorExt.

4 REF = + V Error DriftExt. REF = + V 2 2ppm/ CBipolar Zero ErrorBipolar Range 10 10mVBipolar Zero Error DriftBipolar Range 2 2ppm/ CUnipolar Zero ErrorUnipolar Ranges 10 10mVUnipolar Zero Error DriftUnipolar Ranges 2 2ppm/ CChannel-to-Channel Matching FSRR ecovery to Rated AccuracyAfter F to CAP11msPower Supply SensitivityVANA = VDIG = VDVD = 5 V 5% 8 8 LSBAC ACCURACYS purious Free Dynamic RangefIN = 20 kHz9096dB5 Total Harmonic DistortionfIN = 20 kHz 90 96dBSignal-to-(Noise+Distortion)fIN = 20 kHz8385dB 60 dB Input2728dBSignal-to-NoisefIN = 20 kHz8385dBChannel-to-Channel IsolationfIN = 20 kHz 110 100 110 100dBFull Power Bandwidth611 MHz 3 dB Input DYNAMICSA perture Delay4040nsTransient ResponseFull-Scale Step11 sOvervoltage Recovery7150150nsREFERENCEI nternal Reference Reference Source Current11 AExternal Reference Voltage Rangefor Specified Reference Current DrainExt.

5 REF = + V100100 ADIGITAL INPUTSL ogic LevelsVIL + + + + + + 10 10 AIIH 10 10 A( 408C to +858C, fS = 200 kHz, VDIG = VANA = +5 V, unless otherwise noted)REV. A 3 AD974 A Grade B GradeParameterConditionsMinTypMaxMinTypM axUnitsDIGITAL OUTPUTSData Format Serial 16 BitsData Coding Straight BinaryVOLISINK = mA+ + = 500 A+4+4 VOutput CapacitanceHigh-Z State1515pFLeakage CurrentHigh-Z StateVOUT = 0 V to VDIG 5 5 APOWER SUPPLIESS pecified PerformanceVDIG+ +5+ + +5+ + +5+ + +5+ DissipationPWRD LOW120120mWPWRD HIGH5050 WTEMPERATURE RANGES pecified PerformanceTMIN to TMAX 40+85 40+85 CNOTES1 LSB means Least Significant Bit.

6 With a 10 V input, one LSB is 305 rms noise at worst case transitions and Error is expressed as the % difference between the actual full-scale code transition voltage and the ideal full-scale transition voltage, and includes the effectof offset error. For bipolar input, the Full-Scale Error is the worst case of either the Full-Scale or +Full-Scale code transition voltage errors. For unipolar inputranges, Full-Scale Error is with respect to the +Full-Scale code transition V reference connected to specifications in dB are referred to a full-scale 10 V Bandwidth is defined as full-scale input frequency at which Signal-to-(Noise + Distortion)

7 Degrades to 60 dB, or 10 bits of to specified performance after a 2 FS input subject to change without SPECIFICATIONSP arameterSymbolMinTypMaxUnitsConvert Pulsewidtht150nsR/C, CS to BUSY Delayt2100nsBUSY LOW sBUSY Delay after End of Conversiont450nsAperture Delayt540nsConversion sAcquisition sThroughput Timet6 + t75 sR/C Low to DATACLK Delayt8220nsDATACLK Periodt9220nsDATA Valid Setup Timet1050nsDATA Valid Hold Timet1120nsEXT. DATACLK Periodt1266nsEXT. DATACLK HIGHt1320nsEXT. DATACLK LOWt1430nsR/C, CS to EXT. DATACLK Setup Timet1520t12 + 5nsR/C to CS Setup Timet1610nsEXT. DATACLK to SYNC Delayt171566nsEXT. DATACLK to DATA Valid Delayt182566nsCS to EXT.

8 DATACLK Rising Edge Delayt1910nsPrevious DATA Valid after CS, R/C sBUSY to EXT. DATACLK Setup Timet215nsFinal EXT. DATACLK to BUSY Rising sA0, A1 to WR1, WR2 Setup Timet2310nsA0, A1 to WR1, WR2 Hold Timet2410nsWR1, WR2 Pulsewidtht2550nsSpecifications subject to change without notic e.(fS = 200 kHz, VDIG = VANA = +5 V, 408C to +858C)REV. AAD974 4 CAUTIONESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readilyaccumulate on the human body and test equipment and can discharge without the AD974 features proprietary ESD protection circuitry, permanent damage mayoccur on Devices subjected to high energy electrostatic discharges.

9 Therefore, proper ESDprecautions are recommended to avoid performance degradation or loss of !ESD SENSITIVE DEVICEABSOLUTE MAXIMUM RATINGS1 Analog InputsVxA, VxB .. 25 VCAP .. +VANA + V to AGND2 VREF .. Indefinite Short to AGND2,Momentary Short to VANAG round Voltage DifferencesDGND, AGND1, AGND2 .. VSupply VoltagesVANA .. +7 VVDIG to VANA .. 7 VVDIG .. +7 VDigital Inputs .. V to VDIG + VInternal Power Dissipation2 PDIP (N), SOIC (R), SSOP (RS) .. 700 mWJunction Temperature .. +150 CStorage Temperature Range N, R .. 65 C to +150 CLead Temperature Range(Soldering 10 sec) .. +300 CNOTES1 Stresses above those listed under Absolute Maximum Ratings may cause perma-nent damage to the device.

10 This is a stress rating only; functional operation of thedevice at these or any other conditions above those indicated in the operationalsection of this specification is not implied. Exposure to absolute maximum ratingconditions for extended periods may affect device is for device in free air:28-Lead PDIP: JA = 100 C/W, JC = 31 C/W28-Lead SOIC: JA = 75 C/W, JC = 24 C/W28-Lead SSOP: JA = 109 C/W, JC = 39 C/WPIN CONFIGURATIONSOIC, DIP AND SSOPTOP VIEW(Not to Scale)2827262524232221201918171615123456 7891011121314AD974 DGNDEXT/INTPWRDVDIGR/CAGND2 REFAGND1V3AV3BV4 ACAPBIPV4 BSYNCDATACLKDATAWR2WR1 CSBUSYV2BV2AV1BV1AA1A0 VANATO OUTPUTPINCL100pFIOL+ 1.