National Instruments E Series SCANCLK Signal

Chapter 4 Signal Connections

DAQCard E Series User Manual 4-26

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National Instruments Corporation

SCANCLK Signal

SCANCLK is an output-only signal that generates a pulse with the

leading edge occurring approximately 50 to 100 ns after an A/D

conversion begins. The polarity of this output is software-selectable

but is typically configured so that a low-to-high leading edge can clock

external analog input multiplexers indicating when the input signal has

been sampled and can be removed. This signal has a 400 to 500 ns

pulse width and is software enabled. Figure 4-12

shows the timing for

the SCANCLK signal,

Figure 4-12.

SCANCLK Signal Timing

tw= 400 to 500 ns

td= 50 to 100 ns

CONVERT*

SCANCLK

Contents

Main Page Important Information This document was created with FrameMaker 4.0.4 WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS Trademarks Page Chapter 4 Signal Connections Page Page Figures Tables About This Manual Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Customer Communication Introduction About the DAQCard E Series What You Need to Get Started LabVIEW and LabWindows/CVI Application Software Software Programming Choices NI-DAQ Driver Software Register-Level Programming Optional Equipment Custom Cabling Unpacking Installation and Configuration Installation Configuration Page National Instruments Corporation 3-1 DAQCard E Series User Manual Hardware Overview DAQ - STC This document was created with FrameMaker 4.0.4 I/O Connector Analog Input Input Mode Input Polarity and Input Range Page Page Considerations for Selecting Input Ranges Dither Chapter 3 Hardware Overview National Instruments Corporation 3-7 DAQCard E Series User Manual d. Dither enabled; average of 50 acquisitions c. Dither enabled; no averaging Dither Figure 3-3. Page Analog Trigger Page Page Digital I/O Timing Signal Routing Programmable Function Inputs DAQCard Clocks Many functions performed by the DAQCard E Series cards require a Signal Connections I/O Connector DAQCard E Series User Manual 4-2 Figure 4-1. I/O Connector Pin Assignment for the DAQCard-AI-16E-4 and DAQCard-AI-16XE-50 National Instruments Corporation 4-3 DAQCard E Series User Manual Table 4-1. I/O Connector Signal Descriptions DAQCard E Series User Manual 4-4 Table 4-1. I/O Connector Signal Descriptions (Continued) National Instruments Corporation 4-5 DAQCard E Series User Manual Table 4-2 shows the I/O signal summary for the DAQCard-AI-16E-4. I/O Signal Summary, DAQCard-AI-16E-4 Table 4-2. I/O Signal Summary, DAQCard-AI-16E-4 (Continued) Table 4-2. National Instruments Corporation 4-7 DAQCard E Series User Manual Table 4-2. I/O Signal Summary, DAQCard-AI-16E-4 (Continued) DAQCard E Series User Manual 4-8 Table 4-3 shows the I/O signal summary for the DAQCard-AI-16XE-50. I/O Signal Summary, DAQCard-AI-16XE-50 Table 4-3. Table 4-3. I/O Signal Summary, DAQCard-AI-16XE-50 (Continued) Analog Input Signal Connections Page Types of Signal Sources Input Configurations Ground-Referenced Signal Sources Floating Signal Sources Figure 4-3 summarizes the recommended input configuration for both types of signal sources. Summary of Analog Input Connections Figure 4-3. Differential Connection Considerations (DIFF Input Configuration) National Instruments Corporation 4-15 DAQCard E Series User Manual Differential Connections for Ground-Referenced Signal Sources Differential Input Connections for Ground-Referenced Signals Figure 4-4. in Figure 4-4. Differential Connections for Nonreferenced or Floating Signal Sources Page Single-Ended Connection Considerations Single-Ended Connections for Floating Signal Sources (RSE Configuration) Single-Ended Connections for Grounded Signal Sources (NRSE Configuration) Common-Mode Signal Rejection Considerations Digital I/O Signal Connections Power Connections Timing Connections Page Programmable Function Input Connections Data Acquisition Timing Connections SCANCLK Signal EXTSTROBE* Signal TRIG1 Signal Page TRIG2 Signal STARTSCAN Signal Page Page CONVERT* Signal AIGATE Signal SISOURCE Signal UISOURCE 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 FREQ_OUT Signal Field Wiring Considerations Calibration Loading Calibration Constants Self-Calibration External Calibration Other Considerations Specifications A DAQCard-AI-16E-4 Analog Input Input Characteristics Page Transfer Characteristics Dynamic Characteristics Amplifier Characteristics Stability Digital I/O Timing I/O Triggers Analog Trigger Power Requirement (from PCMCIA I/O channel) Digital Trigger Physical Environment DAQCard-AI-16XE-50 Analog Input Input Characteristics Transfer Characteristics Amplifier Characteristics Dynamic Characteristics Stability Digital I/O Timing I/O Page B Appendix B Optional Cable Connector Descriptions DAQCard E Series User Manual B-2 Figure B-1. 68-Pin AI Connector Pin Assignments Appendix B Optional Cable Connector Descriptions 50-Pin AI Connector Pin Assignments Figure B-2. PC Card Questions and Answers C Configuration Operation Resources Page Resource Conflicts Common Questions D General Information Installation and Configuration Analog Input and Output Timing and Digital I/O Page Page Power-Management Modes E Page Customer Communication FTP Support Electronic Services F Bulletin Board Support Fax and Telephone Support Telephone Fax FaxBack Support E-Mail Support (currently U.S. only) Technical Support Form DAQCard E Series Hardware and Software Configuration Form Other Products National Instruments Products Documentation Comment Form Glossary Symbols A C B D E F H G Page P S R T V U W B A Numbers C D E F G I H L P O N Page Q S R Page T