Rainbow-electronics ADC1251 Manual do Utilizador

TL/H/11025ADC12451 Dynamically-Tested Self-Calibrating 12-BitPlus Sign A/D Converter with Sample-and-HoldDecember 1994ADC12451 Dynamically-Tested Self

Timing DiagramsAuto-Cal CycleTL/H/11025–16Using WR Control to Start a Conversion with Auto-Zero (CALe1, AZe0)TL/H/11025–1710

Timing Diagrams (Continued)Using WRControl to Start a Conversion without Auto-Zero (CAL 1, AZe1)TL/H/11025–18Using S/H Control to Start a Conversion w

1.0 Pin DescriptionsDVCC(24),The digital and analog positive power supplyAVCC(4)pins. The digital and analog power supplyvoltage range of the ADC12451

2.0 Functional Description (Continued)A conversion sequence can also be controlled by the S/Hand CSinputs. Taking CS and S/H low starts the acquisitio

3.0 Analog Considerations (Continued)TL/H/11025–20FIGURE 4a. Low Drift Extremely Stable Reference CircuitTL/H/11025–21Errors without any trims:25§Cb40

3.0 Analog Considerations (Continued)3.5 INPUT BYPASS CAPACITORSAn external capacitor can be used to filter out any noise dueto inductive pickup by a

4.0 Dynamic Performance (Continued)Effective number of bits can also be useful in describing theA/D’s noise performance. An ideal A/D converter will h

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ADC12451 Dynamically-Tested Self-Calibrating 12-BitPlus Sign A/D Converter with Sample-and-HoldPhysical Dimensions inches (millimeters)Order Number AD

Absolute Maximum Ratings (Notes1&2)If Military/Aerospace specified devices are required,please contact the National Semiconductor SalesOffice/Dist

Converter Electrical Characteristics (Continued)The following specifications apply for VCCeDVCCeAVCCea5.0V, Vbeb5.0V, VREFea5.0V, using S/H input forc

Digital and DC Electrical CharacteristicsThe following specifications apply for DVCCeAVCCea5.0V, Vbeb5.0V, VREFea5.0V, and fCLKe3.5 MHz unlessotherwis

AC Electrical Characteristics (Continued)The following specifications apply for DVCCeAVCCea5.0V, Vbeb5.0V, tretfe20 ns unless otherwise specified.Bold

Electrical Characteristics (Continued)Note 7: A diode exists between AVCCand DVCCas shown below.TL/H/11025–5To guarantee accuracy, it is required that

Electrical Characteristics (Continued)TL/H/11025–7FIGURE 1b. Simplified Error Curve vs Output Code without Auto-Cal or Auto-Zero CyclesTL/H/11025–8FIG

Typical Performance Characteristics (Continued)Clock FrequencyLinearity Error vsAmbient TemperatureFull Scale Error Change vsInput Source ImpedanceNoi

Typical Performance Characteristics (Continued)with 10 kHz Sine Wave InputUnipolar Spectral Responsewith 20 kHz Sine Wave InputUnipolar Spectral Respo