Rainbow-electronics ADC1241 Manual de usuario Pagina 1

TL/H/10554ADC1241 Self-Calibrating 12-Bit Plus Sign mP-Compatible A/D Converter with Sample-and-HoldNovember 1994ADC1241 Self-Calibrating 12-Bit PlusS

1.0 Pin DescriptionsDVCC(28),The digital and analog positive power supplyAVCC(4)pins. The digital and analog power supplyvoltage range of the ADC1241

2.0 Functional Description (Continued)Digital Control InputsA/D FunctionCS WR RD CAL AZßß 1 1 1 Start Conversion without Auto-Zeroß 1 ß 1 1 Read Conve

3.0 Analog Considerations (Continued)TL/H/10554–18FIGURE 3. Analog Input Equivalent CircuitFor absolute accuracy, where the analog input varies be-twe

4.0 Dynamic PerformanceMany applications require the A/D converter to digitize acsignals, but the standard dc integral and differential nonlin-earity

ADC1241 Self-Calibrating 12-Bit Plus Sign mP-Compatible A/D Converter with Sample-and-HoldPhysical Dimensions inches (millimeters)Order Number ADC1241

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

Digital and DC Electrical CharacteristicsThe following specifications apply for VCCeDVCCeAVCCea5.0V, Vbeb5.0V, VREFea5.0V, and fCLKe2.0 MHzunless othe

AC Electrical CharacteristicsThe following specifications apply for DVCCeAVCCea5.0V, Vbeb5.0V, tretfe20 ns unless otherwise specified.Boldface limits

AC Electrical Characteristics (Continued)Note 7: A diode exists between AVCCand DVCCas shown below.TL/H/10554–4To guarantee accuracy, it is required t

AC Electrical Characteristics (Continued)TL/H/10554–6FIGURE 1b. Simplified Error Curve vs Output Code Without Auto-Cal or Auto-Zero CyclesTL/H/10554–7

Typical Performance Characteristics (Continued)Linearity Error vs VREFFrequencyLinearity Error vs ClockAmbient TemperatureFull Scale Error Change vsIn

Test CircuitsTL/H/10554–9TL/H/10554–11TL/H/10554–10TL/H/10554–12FIGURE 2. TRI-STATE Test Circuits and WaveformsTiming DiagramsAuto-Cal Cycle (CSe1, WR

Timing Diagrams (Continued)Normal Conversion with Auto-Zero (CALe1, AZe0)TL/H/10554–14Normal Conversion without Auto-Zero (CALe1, AZe1)TL/H/10554–159