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CHAPTER 3 PIN FUNCTION (
µ
PD78078 SUBSERIES)
3.2.21 VDD
Positive power supply pin
3.2.22 V
SS
Ground potential pin
3.2.23 V
PP (
µ
PD78P078 only)
High-voltage apply pin for PROM programming mode setting and program write/verify. Connect directly to VSS
in normal operating mode.
3.2.24 IC (Mask ROM version only)
The IC (Internally Connected) pin is provided to set the test mode to check the
µ
PD78078 at delivery. Connect
it directly to the VSS with the shortest possible wire in the normal operating mode.
When a voltage difference is produced between the IC pin and VSS pin because the wiring between those two pins
is too long or an external noise is input to the IC pin, the user’s program may not run normally.
• Connect IC pins to V
SS pins directly.
VSS IC
As short as possible