X9241A
A.C. CONDITIONS OF TEST
Guidelines for Calculating
Typical Values of Bus Pull-Up Resistors
Input pulse levels
V
x 0.1 to V x 0.9
CC
CC
Input rise and fall times
Input and output timing levels
10ns
120
V
I
CC MAX
R
R
=
=1.8KΩ
MIN
V
x 0.5
CC
100
80
OL MIN
t
R
=
MAX
SYMBOL TABLE
C
BUS
Max.
Resistance
60
40
20
0
WAVEFORM
INPUTS
OUTPUTS
Must be
steady
Will be
steady
Min.
Resistance
May change
from LOW
to HIGH
Will change
from LOW
to HIGH
20 40 60 80
120
100
0
Bus Capacitance (pF)
May change
from HIGH
to LOW
Will change
from HIGH
to LOW
DCP Wiper Current De-rating Curve
Don’t Care:
Changes
Allowed
Changing:
State Not
Known
7
6
5
4
3
N/A
Center Line
is High
Impedance
Equivalent A.C. Test Circuit
2
1
0
5V
1533Ω
0
10
20
30
40 50
60 70
80 90
Ambient Temperature (°C)
SDA Output
100pF
Circuit #3 SPICE Macro Model
Macro Model
R
H
TOTAL
R
R
H
L
C
C
L
10pF
C
W
10pF
25pF
R
W
Characteristics subject to change without notice. 12 of 18
REV 1.1.13 12/09/02
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