Digi NS7520 User Manual

w w w . d i g i . c o m

 

 

 

 

 

 

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P i n o u t   a n d   P a c k a g i n g

Each pinout table applies to a specific interface and contains the following 
information:

NO CONNECT

 as a description for a pin means do not connect to this pin.

The 177th pin (package ball) is for alignment of the package on the PCB.

Signal

The pin name for each I/O signal. Some signals have multiple function modes and 
are identified accordingly. The mode is configured through firmware using one or 
more configuration registers.

Pin

The pin number assignment for a specific I/O signal.

 

U next to the pin number indicates that the pin is a pullup resistor (input 

current source). 

 

D next to the pin number indicates that the pin is a pulldown resistor (input 

current sink). 

 

No value next to the pin indicates that the pin has neither a pullup nor 

pulldown resistor. 

See Figure 28, "Internal pullup characteristics," on page 264 and Figure 29, 
"Internal pulldown characteristics," on page 264 for an illustration of the 
characteristics of these pins. Use the figures to select the appropriate value of the 
complimentary resistor to drive the signal to the opposite logic state. For those 
pins with no pullup or pulldown resistor, you must select the appropriate value per 
your design requirements.

_

An underscore (bar) indicates that the pin is active low.

I/O

The type of signal — input, output, or input/output.

OD

The output drive strength of an output buffer. The NS7520 uses one of three 
drivers:

 

2 mA

 

4 mA

 

8 mA