Rainbow-electronics ADC12062 Manual do Utilizador Página 1

TL/H/11490ADC12062 12-Bit, 1 MHz, 75 mW A/D Converterwith Input Multiplexer and Sample/HoldDecember 1994ADC1206212-Bit, 1 MHz, 75 mW A/D Converterwith

Functional DescriptionThe ADC12062 performs a 12-bit analog-to-digital conver-sion using a 3 step flash technique. The first flash deter-mines the six

Functional Description (Continued)tap points between (*/8)VREFand (±/8)VREF. This overlap of((/16)VREFwill automatically cancel a Voltage Estimator er

Applications Information (Continued)TL/H/11490– 16FIGURE 6. ADC Control Logic2.0 THE ANALOG INPUTThe analog input of the ADC12062 can be modeled as tw

Applications Information (Continued)TL/H/11490– 18FIGURE 8. Buffering the Input with an LM6361 High Speed Op AmpAnother benefit of using a high speed

Applications Information (Continued)3.0 ANALOG MULTIPLEXERThe ADC12062 has an input multiplexer that is controlled bythe logic level on pin S0 when EO

Applications Information (Continued)Since the current flowing through the SENSE lines is essen-tially zero, there is negligible voltage drop across RS

Applications Information (Continued)5.0 POWER SUPPLY CONSIDERATIONSThe ADC12062 is designed to operate from a singlea5Vpower supply. There are two ana

Applications Information (Continued)edge) of an MM74HC4538 one-shot. The 1k resistor and 12pF capacitor set the pulse length to approximately 100 ns.T

Applications Information (Continued)AC Coupling Bipolar InputsTL/H/11490– 2618

Physical Dimensions inches (millimeters)Plastic Leaded Chip Carrier (V)Order Number ADC12062BIV, ADC12062CIVNS Package Number V44A19

Absolute Maximum Ratings (Notes 1, 2)If Military/Aerospace specified devices are required,please contact the National Semiconductor SalesOffice/Distri

ADC12062 12-Bit, 1 MHz, 75 mW A/D Converterwith Input Multiplexer and Sample/HoldPhysical Dimensions inches (millimeters) (Continued)Plastic Quad Flat

Dynamic Characteristics (Note 10) The following specifications apply for DVCCeAVCCea5V,VREFa(SENSE)ea4.096V, VREFb(SENSE)eAGND, RSe25X,fINe100 kHz, 0

AC Electrical Characteristics The following specifications apply for DVCCeAVCCea5V,VREFa(SENSE)ea4.096V, VREFb(SENSE)eAGND, and fse1 MHz, unless other

Note 5: Human body model, 100 pF discharged through a 1.5 kX resistor. Machine model ESD rating is 200V.Note 6: See AN-450 ‘‘Surface Mounting Methods

Typical Performance CharacteristicsReference VoltageError Change vsOffset and Fullscalevs Reference VoltageLinearity Error ChangeInput VoltageMux ON R

Typical Performance Characteristics (Continued)(Through Mux)SINAD vs Input Frequency(Through Mux)SNR vs Input Frequency(Through Mux)THD vs Input Frequ

Timing Diagrams (Continued)TL/H/11490– 10FIGURE 2. High Speed Interface Timing (MODEe1, OEe1, CSe0, RDe0)TL/H/11490– 11FIGURE 3. CS Setup and Hold Tim

Pin DescriptionsAVCCThese are the two positive analog supplyinputs. They should always be connectedto the same voltage source, but arebrought out sepa