CHAPTER 2 PIN FUNCTIONS
2.2.17 VDD
This is the positive power supply pin.
2.2.18 VSS
This is the ground pin.
2.2.19 VPP (µPD78F9436, 78F9456 only)
A high voltage should be applied to this pin when the flash memory programming mode is set and when the
program is written or verified.
Directly connect this pin to VSS in the normal operation mode.
2.2.20 IC (mask ROM version only)
The IC (Internally Connected) pin is used to set the µPD789426, 789436, 789446, and 789456 Subseries in the
test mode before shipment. In the normal operation mode, directly connect this pin to the VSS pin with as short a
wiring length as possible.
If a potential difference is generated between the IC pin and VSS pin due to a long wiring length, or an external
noise superimposed on the IC pin, the user program may not run correctly.
• Directly connect the IC pin to the VSS pin.
V
SS IC
Keep short
User’s Manual U15075EJ1V0UM00
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NEC [ NEC ]
