Datasheet

CHAPTER 2 PIN FUNCTIONS
User’s Manual U18172EJ3V0UD
26
2.2.6 EXCLK ( μ PD78F950x)
This is the external clock input pin for the main system clock.
EXCLK functions as P23. For the setting method for pin functions, see CHAPTER 15 OPTION BYTE.
Caution The P23/EXCLK pin is pulled down during reset.
2.2.7 V
DD
This is the positive power supply pin.
In
μ PD78F920x, VDD functions alternately as the A/D converter reference voltage input. When using the A/D
converter, stabilize V
DD at the supply voltage used (2.7 to 5.5 V).
2.2.8 V
SS
This is the ground pin.
In
μ PD78F920x, VSS functions alternately as the ground potential of the A/D converter. Be sure to connect VSS to a
stabilized GND (= 0 V).