National Instruments NI 6115, NI 6120 E

Glossary

NI 6115/6120 User Manual G-4 ni.com

DAQ-STC data acquisition system timing controller—an application-specific

integrated circuit (ASIC) for the system timing requirements of a general

A/D and D/A system, such as a system containing the National

Instruments E Series devices

dB decibel—the unit for expressing a logarithmic measure of the ratio of

twosign al levels: dB = 20log10 V1/V2, for signals in volts

DC direct current

DGND digital ground signal

DI digital input

DIFF differential mode—an analog input mode consisting of two terminals,

both of which are isolated from computer ground, whose difference is

measured

DIO digital input/output

DIP dual inline package

dithering the addition of Gaussian noise to an analog input signal for the purpose

of increasing the resolution of a measurement when using averaging

DMA direct memory access—a method by which data can be transferred

to/from computer memory from/to a device or memory on the bus while

the processor does something else; the fastest method of transferring data

to/from computer memory

DNL differential nonlinearity—a measure in least significant bit of the

worst-case deviation of code widths from their ideal value of 1 LSB

DO digital output

E

EEPROM electrically erasable programmable read-only memory—ROM that can

be erased with an electrical signal and reprogrammed

ENOB effective number of bits

Contents

Main Page Important Information Warranty Copyright Trademarks Patents Compliance FCC/Canada Radio Frequency Interference Compliance Determining FCC Class FCC/DOC Warnings Class A Compliance to EU Directives Contents Chapter 4 Connecting Signals Page About This Manual Conventions National Instruments Documentation Related Documentation Introduction About the NI 6115/6120 Using PXI with CompactPCI What You Need to Get Started Software Programming Choices NI-DAQ National Instruments ADE Software Optional Equipment Custom Cabling Unpacking Safety Information Page Page Installing and Configuring the NI 6115/6120 Installing the Software Installing the Hardware Page Configuring the Device National Instruments Corporation 3-1 NI 6115/6120 User Manual Hardware Overview DAQ - STC RTSI Bus Figure 3-1. NI 6115 Block Diagram Analog Input The following sections describe in detail each AI category. Input Mode Note The inputs are differential only in the sense that the ground loops are broken. I/O Connector Input Polarity and Input Range Considerations for Selecting Input Ranges Input Coupling Analog Output Analog Trigger Figure 3-3. Analog Trigger Block Diagram for the NI 6115/6120 Figure 3-4. Below-Low-Level Analog Triggering Mode Page Antialiasing Filters Phase-Locked Loop Circuit Correlated Digital I/O Timing Signal Routing Page Programmable Function Inputs Device and RTSI Clocks RTSI Triggers Page Figure 3-13. PXI RTSI Bus Signal Connections Connecting Signals I/O Connector Figure 4-1. I/O Connector Pin Assignment for the NI 6115/6120 I/O Connector Signal Descriptions Table 4-2. Signal Descriptions for I/O Connector Pins Table 4-2. Signal Descriptions for I/O Connector Pins (Continued) Table 4-3. Analog I/O Signal Summary for the NI 6115 Table 4-2. Signal Descriptions for I/O Connector Pins (Continued) Table 4-4. Analog I/O Summary for the NI 6120 Table 4-5. Digital I/O Signal Summary Types of Signal Sources Floating Signal Sources Table 4-5. Digital I/O Signal Summary (Continued) Ground-Referenced Signal Sources Connecting Analog Input Signals Connections for Ground-Referenced Signal Sources * Figure 4-2. Pseudodifferential Input Connections on the NI 6115 forGro und-Referenced Signals Figure 4-3. Pseudodifferential Input Connections on the NI 6120 forGro und-Referenced Signals Connections for Nonreferenced or Floating Signal Sources * Figure 4-4. Differential Input Connections on the NI 6115 for Nonreferenced Signals Common-Mode Signal Rejection Considerations Working Voltage Range Connecting Analog Output Signals Connecting Digital I/O Signals Correlating DIO Signal Connections Page Power Connections Connecting Timing Signals Page Programmable Function Input Connections DAQ Timing Connections TRIG1 Signal TRIG2 Signal Page STARTSCAN Signal Page CONVERT* Signal AIGATE Signal SISOURCE Signal SCANCLK Signal EXTSTROBE* Signal Waveform Generation Timing Connections WFTRIG Signal UPDATE* 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 Figure4-34 shows the timing requirements for GPCTR1_OUT. Figure 4-35. GPCTR1_OUT Signal Timing Figure 4-36. GPCTR Timing Summary GPCTR1_UP_DOWN Signal FREQ_OUT Signal Field Wiring Considerations Calibration Loading Stored Calibration Constants Self-Calibration External Calibration Page A Specifications Analog Input Input Characteristics DC Transfer Characteristics Table A-1. NI 6115 Analog Input DC Accuracy Information Table A-2. NI 6120 Analog Input DC Accuracy Information Dynamic Characteristics Table A-4. NI6120 Analog Input Dynamic Charac teristics Figure A-1. NI 6115 Total Harmonic Distortion Plus Noise (THD+N) Figure A-2. NI 6120 Total Harmonic Distortion Plus Noise (THD+N) Figure A-3. NI6115 High-Voltage THD + N Figure A-4. NI 6120 High-Voltage THD+ N Figure A-5. NI 6115 THD + N with Filters Stability Analog Output Output Characteristics DC Transfer Characteristics Voltage Output Dynamic Characteristics Stability Digital I/O Timing I/O Triggers Analog Trigger Page Safety Maximum Working Voltage Electromagnetic Compatibility B Common Questions General Information Installing and Configuring the Device Analog Input and Output Page Timing and Digital I/O Page C Technical Support and Professional Services Glossary Numbers/Symbols A B C D E F G H I K L M N O P R S T U V W Index Numerics A B C D E F G H I K L M N O P Q R S Page T U V W