National Instruments PC-LPM-16/PnP 사용자 설명서

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Chapter 4     Signal Connections
 
 
 National Instruments Corporation
4-7
PC-LPM-16/PnP User Manual
 
Figure 4-3.  
 
Analog Input Signal Connections
 
Figure 4-3 shows the connections of the digital input port and digital 
output port. Digital input applications include receiving TTL signals 
and sensing external device states such as the switch in Figure 4-3. 
Digital output applications include sending TTL signals and driving 
external devices such as the LED shown in Figure 4-3.
 
Power Connections
 
Pin 49 of the I/O connector supplies +5 V from the computer I/O 
channel power supply. Pin 20 of the I/O connector supplies +12 V from 
the computer I/O channel power supply. The -12 V is supplied from the 
computer I/O power supply with a resistor in series. These pins are 
referenced to DGND and can be used to power external digital circuitry. 
The +5 V supply at the I/O connector has a 1.0 A protection fuse in 
series. The +12 V supply at the I/O connector has a 0.5 A protection 
TTL Signal
Digital
Input
Port
Digital
Output
Port
22 DIN 0
19
DGND
I/O Connector
PC-LPM-16PnP
LED
+5 V
+5 V
29 DIN 7
30 DOUT 0
Debounced Switch*
*Complex switch circuitry is not shown here in order to simplify the figure.
 
a.Book : h.chapter 4  Page 7  Wednesday, November 20, 1996  6:36 PM