µ
PD75P308
9
TYPE M-C
data
output
disable
P.U.R.
enable
V
DD
P.U.R.
IN/OUT
P–ch
N-ch
P.U.R. : Pull–Up Resistor
1.4 NOTES ON USING P00/INT4 AND RESET PINS
In addition to the functions shown in sections 1.1 and 1.2, the P00/INT4 and RESET pins also have a function
to set a test mode (for IC testing) in which the internal operations of the
µ
PD75P308 are tested.
When a voltage higher than V
DD
is applied to either of these pins, the test mode is set. This means that, even
during ordinary operation, the
µ
PD75P308 may be set in the test mode if a noise exceeding V
DD
is applied.
For example, if the wiring length of the P00/INT4 or RESET pin is too long, noise superimposed on the wiring
line of the pin may cause the above problem.
Therefore, keep the wiring length of these pins as short as possible to suppress the noise; otherwise, take noise
preventive measures as shown below by using external components.
•
Connect diode with low V
F
between V
DD
and P00/INT4, RESET pin
•
Connect capacitor between V
DD
and P00/INT4, RESET pin
V
DD
V
DD
V
DD
V
DD
P00/INT4, RESET
Diode with
low V
F
P00/INT4, RESET