M80C51FB
All other pins disconnected
271172 – 8
Figure 7 ICC Load Circuit Power Down Mode
VCC e 2 0V to 5 5V
271172 – 9
Figure 8 Clock Signal Waveform for ICC Tests in Active and Idle Modes TCLCH e TCHCL e 5 ns
EXPLANATION OF THE AC SYMBOLS
Each timing symbol has 5 characters The first char-
acter is always a ‘T’ (stands for time) The other
characters depending on their positions stand for
the name of a signal or the logical status of that
signal The following is a list of all the characters and
what they stand for
A Address
C Clock
D Input Data
H Logic level HIGH
I Instruction (program memory contents)
L Logic level LOW or ALE
P PSEN
Q Output Data
R RD signal
T Time
V Valid
W WR signal
X No longer a valid logic level
Z Float
For example
TAVLL e Time from Address Valid to ALE Low
TLLPL e Time from ALE Low to PSEN Low
8