ADC1205 National Semiconductor, ADC1205 Datasheet
ADC1205
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ADC1205 Summary of contents
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... General Description The ADC1205 and ADC1225 are CMOS 12-bit plus sign successive approximation A D converters ADC1205 outputs the 13-bit data result in two 8-bit bytes formatted high-byte first with sign extended The 28-pin ADC1225 outputs a 13-bit word in parallel for direct inter- face to a 16-bit data bus Negative numbers are represented in 2’ ...
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... C (Notes Parameter Conditions CONVERTER CHARACTERISTICS Linearity Error Unipolar Input ADC1205CCJ ADC1225CCD Range ADC1205CCJ-1 ADC1225CCD-1 (Note 11) Unadjusted Zero Error Unipolar Input Range Unadjusted Positive and Negative Unipolar Input Full-Scale Error Range Negative Full-Scale Error Unipolar Input Range Full ...
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... V 5 05V a IN 05V V 5 05V a IN all other limits T T MIN MAX A J ADC1205CCJ-1 ADC1225CCD-1 Limit Tested Design Typ Units Limit Limit (Note 8) (Note 9) (Note 10) GND-0 05 GND ...
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... V 5 05V a IN 05V V 5 05V a IN all other limits T T MIN MAX A J ADC1205CCJ-1 ADC1225CCD-1 Limit Tested Design Typ Units Limit Limit (Note 8) (Note 9) (Note 10 ...
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AC Electrical Characteristics Note 4 Two on-chip diodes are tied to each analog input as shown below Errors in the A D conversion can occur if these diodes are forward biased more than 50 mV This means that if AV ...
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FIGURE 1b Simplified Error Curve vs Output Code Without Zero and Fullscale Adjustment FIGURE 1c Simplified Error Curve vs Output Code after Zero Fullscale Adjustment FIGURE 2 TRI-STATE Test Circuits and Waveforms TL H 5676 – ...
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Timing Diagrams FIGURE 3 Timing Diagram TL H 5676 – 13 FIGURE 4 Ready Out TL H 5676 – 14 FIGURE 5 Data Out 5676 – 15 ...
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8 ...
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... IN( ) the ADC1205 The ADC1205’s STATUS pin makes it possible to read the conversion status and the state of the ‘byst’ flip-flop With RD STATUS and CS low this information appears on the data bus The ‘byst’ status appears on pin 18 (DB2 DB10) A low output on pin 18 indicates that the next data read will ...
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Functional Description (Continued) TABLE II Status Bit Locations and Meanings (Continued) Status Status Bit Bit Meaning Location DB1 EOC ‘‘High’’ indicates that the conversion is completed and data is transferred to the output latch DB0 INT ‘‘High’’ indicates that it ...
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Functional Description (Continued) FIGURE 10 FIGURE 11 FIGURE 5676 – 5676 – 5676 – 27 ...
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Functional Description (Continued) When using this method of conversion only one strobe is necessary and the rising edge can be used to read the current conversion results These methods reduce the throughput time of the conversion since ...
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... In general the magnitude of the reference voltage will re- quire an initial adjustment to null out full-scale errors 5 0 THE ANALOG INPUTS 5 1 DIFFERENTIAL VOLTAGE INPUTS AND COMMON MODE REJECTION The differential inputs of the ADC1225 and ADC1205 actu- ally reduce the effects of common-mode input noise i e signals common to both V and V a ...
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Functional Description (Continued) A simpler although slightly less accurate approach is to ground V and V and adjust for all zeros at the a b IN( ) IN( ) output Error will be well under LSB if the adjustment is ...
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Typical Applications (Continued) Diodes are 1N914 Operating with Ratiometric Transducers XDR Protecting the Input 5676 – ...
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Typical Applications (Continued) Bipolar Input Temperature Converter a b 150 with resolution Note resistors are 1% metal film types Strain Gauge Converter with 025% Resolution and Single Power Supply Note 1) resistors are 1% ...
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... Ordering Information Temperature Range Non-Linearity 0 024% ADC1205CCJ-1 Package Outline Physical Dimensions inches (millimeters) Order Number ADC1205CCJ-1 or ADC1205CCJ ADC1225CCD-1 ADC1205CCJ J24A D28D Ceramic Dual-In Line Package (J) NS Package Number J24A ADC1225CCD J24A D28D ...
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