Datasheet

REV. –4–
ADM1485
Test Circuits
V
OD
R
R
V
OC
Test Circuit 1. Driver Voltage Measurement
V
OD3
60⍀
375⍀
375⍀
V
TST
Test Circuit 2. Driver Voltage Measurement
R
LDIFF
A
B
C
L1
C
L2
Test Circuit 3. Driver Propagation Delay
DE
0V OR 3V
DE IN
A
B
S1
C
L
V
OUT
R
L
S2
V
CC
Test Circuit 4. Driver Enable/Disable
RE
A
B
C
L
V
OUT
Test Circuit 5. Receiver Propagation Delay
RE
+1.5V
RE IN
S1
C
L
V
OUT
R
L
S2
V
CC
–1.5V
Test Circuit 6. Receiver Enable/Disable
Switching Characteristics
3V
0V
B
A
0V
–V
O
V
O
90% POINT
10% POINT
t
R
t
SKEW
= 円 t
PLH
– t
PHL
円
1/2VO
t
PLH
1.5V
1.5V
t
PHL
90% POINT
10% POINT
t
F
V
O
Figure 1. Driver Propagation Delay, Rise/Fall Timing
DE
A, B
A, B
1.5V
2.3V
2.3V
t
ZH
t
ZL
1.5V
3V
0V
V
OL
V
OH
0V
V
OL
+ 0.5V
V
OH
– 0.5V
t
HZ
t
LZ
Figure 2. Driver Enable/Disable Timing
A, B
RO
0V
t
PLH
1.5V
0V
t
PHL
1.5V
V
OH
V
OL
t
SKEW
= 円 t
PLH
– t
PHL
円
Figure 3. Receiver Propagation Delay
RE
R
R
1.5V
1.5V
1.5V
t
ZH
t
ZL
1.5V
3V
0V
V
OL
V
OH
V
OL
+ 0.5V
V
OH
– 0.5V
t
HZ
t
LZ
O/P LOW
O/P HIGH
0V
Figure 4. Receiver Enable/Disable Timing
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