I - 29
Chapter 1 Overview
Precautions
1-6-2 Unused Pins
Unused Pins (only for input)
Insert 10 kΩ to 100 kΩ resistor to unused pins (only for input) for pull-up or pull-down. If the input is
unstable, Pch transistor and Nch transistor of input inverter are on, and through current goes to the input
circuit. That increases current consumption and causes power supply noise.
Figure 1-6-1 Unused Pins (only for input)
Figure 1-6-2 Input Inverter Organization and Characteristics
10 kΩ to 100 kΩ
Input
Input pin
Input
Input pin
10 kΩ to 100 kΩ
Input
Pch
Input pin
Nch
3
0 Input voltage
(V
DD=3 V)
Current
Through current
Input inverter characteristics
Input inverter organization