National Instruments 700 Chapter 4 Theory of Operation

© National Instruments Corporation 4-1 DAQCard-700 User Manual
Chapter 4
Theory of Operation
This chapter includes an overview of the DAQCard-700 and explains the operation of each
functional unit making up the DAQCard-700.
Functional Overview
The block diagram in Figure 4-1 shows a functional overview of the DAQCard-700.
FROM A/D FIFO
CLK<1..2>
OUT<0..2>
GATE<0..2>
I/O Connector
OUT0 EXTCONV*
3
3
8
8
-12 V
To Analog Circuit
+5 V +5 V
+12 V
12-Bit
Sampling 
ADC
512-Word 
FIFO
PCMCIA
I/O 
Channel 
Interface
Buffer
PCMCIA I/O Channel
Instrumentation
Amplifier
Input
Mux2 
4-Channel
+
-
Input
Mux1
Dual
8-Channel
Single-
Ended
Scanning Counter
8
8
A/D Timing
MSM82C54
Interrupt 
Interface
Digital
I/O
DC-DC
Converter
To Analog Circuit
2
1 A Resettable Fuse
Figure 4-1. DAQCard-700 Block Diagram