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National Instruments PCI-4451, PCI-4452 Figure 6-5. Signal Spectra in the DAC

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Chapter 6 Theory of Analog Operation

National Instruments Corporation 6-11 PCI-4451/4452 User Manual

of eight times the sample rate, as shown in Figure 6-5c. Still, images remain and they must be filtered out. Each output channel of the PCI-4451 has discrete-time (switched-capacitor) and continuous-time analog filters that remove the high-frequency images, as shown in Figure6-5d.

Figure 6-5. Signal Spectra in the DAC

Fs8 Fs16 Fs

Baseband Signal Images

a. Spectrum of Sampled Signal

b. Spectrum of Signal After Digital Filter

Frequency

Amplitude

Fs8 Fs16 Fs

Baseband Signal Images After the Digital Filter

Frequency

AmplitudeAmplitude

c. Spectrum of Signal After DAC

Fs8 Fs16 Fs

Baseband Signal Images After the DAC

Frequency

Amplitude

d. Spectrum of Signal After Analog Filters

Fs8 Fs16 Fs

Baseband Signal

Frequency

User.book Page 11 Tuesday, April 14, 1998 10:20 AM

Contents

Main Page Important Information Warranty Copyright Trademarks WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS Contents Chapter 4 Signal Connections Page Figures Tables About This Manual Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Customer Communication Introduction What You Need to Get Started Unpacking Software Programming Choices National Instruments Application Software Optional Equipment Custom Cabling Page Installation and Configuration Software Installation Hardware Installation Device Configuration National Instruments Corporation 3-1 PCI-4451/4452 User Manual Hardware Overview Figure 3-1. Digital Function Block Diagram Chapter 3 Hardware Overview User.book Page 2 Tuesday, April 14, 1998 10:20 AM DAC0 Figure 3-2. Analog Function Block Diagram National Instruments Corporation PCI-4451/4452 User Manual 3-2 Serial Data Manager Analog Bus Analog Input Input Mode Input Coupling Input Polarity and Input Range Considerations for Selecting Input Ranges Analog Output Output Mode Output Polarity and Output Range Trigger Page Page RTSI Triggers Digital I/O Timing Signal Routing Programmable Function Inputs Device and RTSI Clocks Selecting Sample/Update Clock Frequency Device Configuration Issues Signal Connections I/O Connectors PCI-4451/4452 User Manual 4-2 National Instruments Corporation Analog I/O Connector Signal Descriptions Figure4-1 shows the analog pin connections for the PCI-4451/4452. Figure 4-1. Analog Pin Connections National Instruments Corporation 4-3 PCI-4451/4452 User Manual Table 4-1. Analog I/O Connector Pin Assignment DAC0OUT +DAC0OUT Output DAC1OUT +DAC1OUT Output PCI-4451/4452 User Manual 4-4 National Instruments Corporation Table 4-2. Analog I/O Signal Summary Digital I/O Connector Signal Descriptions Figure4-2 shows the digital pin connections for the PCI-4451/4452. Figure 4-2. Digital Pin Connections Refer to AppendixB, Pin C onnections, for the digital pin connections of the 68-pin connector. PCI-4451/4452 User Manual 4-6 Table 4-3. Digital I/O Connector Pin Assignment National Instruments Corporation 4-7 PCI-4451/4452 User Manual Table 4-3. Digital I/O Connector Pin Assignment (Contin ued) PCI-4451/4452 User Manual 4-8 National Instruments Corporation Table 4-4. Digital I/O Signal Summary Analog Input Signal Connections Types of Signal Sources Floating Signal Sources Ground-Referenced Signal Sources Analog Output Signal Connections Analog Power Connections Digital I/O Signal Connections Page Digital Power Connections Timing Connections Programmable Function Input Connections Acquisition Timing Connections PFI0/TRIG1 (EXT_TRIG) Signal PFI1/TRIG2 (PRETRIG) Signal CONVERT* Signal EXTSTROBE* Signal Waveform Generation Timing Connections WFTRIG Signal UPDATE* Signal General-Purpose Timing Signal Connections GPCTR0_SOURCE Signal GPCTR0_GATE Signal GPCTR0_OUT Signal GPCTR0_UP_DOWN Signal GPCTR1_SOURCE Signal GPCTR1_GATE Signal GPCTR1_OUT Signal GPCTR1_UP_DOWN Signal Page FREQ_OUT Signal Field Wiring Considerations Page Calibration Loading Calibration Constants Self-Calibration External Calibration Traceable Recalibration Theory of Analog Operation Functional Overview Analog Input Circuitry Input Coupling Antialias Filtering Page Chapter 6 Theory of Analog Operation Figure 6-1. Input Frequency Response National Instruments Corporation 6-5 PCI-4451/4452 User Manual Page Page The ADC Noise Analog Output Circuitry Anti-Image Filtering Chapter 6 Theory of Analog Operation National Instruments Corporation 6-11 PCI-4451/4452 User Manual Figure 6-5. Signal Spectra in the DAC The DAC Mute Feature A Specifications Analog Input Channel Characteristics Transfer Characteristics Amplifier Characteristics Dynamic Characteristics Onboard Calibration Reference Analog Output Channel Characteristics Transfer Characteristics Voltage Output Characteristics Dynamic Characteristics Digital I/O Timing I/O Triggers Analog Trigger Digital Trigger Bus Interface Power Requirement Physical Environment Page Appendix B Pin Connections Figure B-1. 68-Pin Digital Connector for any Digital Accessor y National Instruments Corporation PCI-4451/4452 User Manual B-2 C Customer Communication Electronic Services Bulletin Board Support FTP Support Fax-on-Demand Support Telephone and Fax Support Country Telephone Fax Technical Support Form PCI-4451/4452 Hardware and Software Configuration Form National Instruments Products Other Products Documentation Comment Form Title: Edition Date: Part Number: Mail to: Technical Publications Fax to: Technical Publications Glossary Numbers/Symbols A Page B C Page D Page E F G H I Page K L M N O P Q R S Page T U V W Z Index Numbers A B C D E F G H I J L M N R S T U V W