168
7663E–8051–10/08
AT89C51RE2
Figure 72. I
CC Test Condition, Idle Mode
Figure 73. ICC Test Condition, Power-down Mode
Figure 74. Clock Signal Waveform for I
CC Tests in Active and Idle Modes
AC Parameters
Explanation of the AC
Symbols
Each timing symbol has 5 characters. The first character is always a “T” (stands for time). The
other characters, depending on their positions, stand for the name of a signal or the logical sta-
tus of that signal. The following is a list of all the characters and what they stand for.
Example:T
AVLL = Time for Address Valid to ALE Low.
T
LLPL = Time for ALE Low to PSEN Low.
(Load Capacitance for port 0, ALE and PSEN = 100 pF; Load Capacitance for all other outputs =
80 pF.)
for each speed range description. To calculate each AC symbols. Take the x value in the corre-
sponding column (-M or -L) and use this value in the formula.
RST
EA
XTAL2
XTAL1
V
SS
V
CC
VCC
ICC
(NC)
P0
VCC
All other pins are disconnected.
CLOCK
SIGNAL
RST
EA
XTAL2
XTAL1
V
SS
V
CC
V
CC
ICC
(NC)
P0
V
CC
All other pins are disconnected.
V
CC-0.5V
0.45V
0.7V
CC
0.2V
CC-0.1
T
CLCH
T
CHCL
TCLCH = TCHCL = 5ns.