Renesas HD6417641 用户手册

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页码 1036
Rev. 4.00  Sep. 14, 2005  Page iv of l 
 
General Precautions on Handling of Product 
1.  Treatment of NC Pins 
Note:  Do not connect anything to the NC pins. 
The NC (not connected) pins are either not connected to any of the internal circuitry or are 
used as test pins or to reduce noise. If something is connected to the NC pins, the 
operation of the LSI is not guaranteed. 
2.  Treatment of Unused Input Pins 
Note:  Fix all unused input pins to high or low level. 
Generally, the input pins of CMOS products are high-impedance input pins. If unused pins 
are in their open states, intermediate levels are induced by noise in the vicinity, a pass-
through current flows internally, and a malfunction may occur. 
3. Processing before Initialization 
Note:  When power is first supplied, the product's state is undefined.  
The states of internal circuits are undefined until full power is supplied throughout the 
chip and a low level is input on the reset pin. During the period where the states are 
undefined, the register settings and the output state of each pin are also undefined. Design 
your system so that it does not malfunction because of processing while it is in this 
undefined state. For those products which have a reset function, reset the LSI immediately 
after the power supply has been turned on. 
4.  Prohibition of Access to Undefined or Reserved Addresses 
Note:  Access to undefined or reserved addresses is prohibited. 
The undefined or reserved addresses may be used to expand functions, or test registers 
may have been be allocated to these addresses. Do not access these registers; the system's 
operation is not guaranteed if they are accessed. 
5.  Treatment of Power Supply (0 V) Pins 
Note:  There should be no voltage difference between the system ground pins (0 V power 
supply), VssQ, Vss, Vss, Vss (PLL1), and Vss (PLL2). 
 
If voltage difference is created between the system ground pins, malfunctions may occur or 
excessive current flows during standby due to through current. Voltage difference should not 
be created between the system ground pins, VssQ, Vss, Vss (PLL1), and Vss (PLL2).