HD64F3437TF16 Datasheet, PDF (599/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

Measurement Conditions for AC Characteristics
5V
LSI
output pin
R_H
C
R_L
C = 90 pF: Ports 1–4, 6, 9, A, B
30 pF: Ports 5, 8
R_L = _{2.4 kΩ}
R_H = _{12 kΩ}
Input/output timing measurement levels
Low: 0.8 V
High: 2.0 V
Figure 23.3 Measurement Conditions for A/C Characteristics
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