Справочник Пользователя для IBM LPCI-COM-8SM

 

 

 

Driver Output Voltage (unloaded) 

  

4V 

6V 

  

  

-4V  -6V 

Driver Output Voltage (loaded) 

LD and LDGND  2V 

  

  

 jumpers in 

-2V    

Driver Output Resistance 

  

  

50Ω 

Driver Output Short-Circuit Current 

  

  

+150 mA 

Driver Output Rise Time 

  

  

10% unit interval 

Receiver Sensitivity 

  

  

+200 mV 

Receiver Common Mode Voltage Range   

  

+7V 

Receiver Input Resistance 

  

  

4KΩ 

 

 RS422 Specification Summary

 
To prevent signal reflections in the cable and to improve noise rejection in both the RS422 and RS485 
mode, the receiver end of the cable should be terminated with a resistance equal to the characteristic 
impedance of the cable. (An exception to this is the case where the line is driven by an RS422 driver that 
is never "tristated" or disconnected from the line. In this case, the driver provides a low internal 
impedance that terminates the line at that end.) 
 
Note

  

You do not have to add a terminator resistor to your cables when you use the card. Termination resistors 
for the RX+ and RX- lines are provided on the card and are placed in the circuit when you install the Ch X 
- LD jumpers. (See the Option Selection section of this manual.) 
 
 
 

Manual LPCI-COM-8SM 

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