SN75177B, SN75178B
DIFFERENTIAL BUS REPEATERS
SLLS002C – D2606, JULY 1985 – REVISED FEBRUARY 1993
PARAMETER MEASUREMENT INFORMATION
R
L
L
2
V
ID
V
OD2
V
R
2
OH
V
OC
+I
– I
OH
OL
V
OL
Figure 1. Driver V
and V
Figure 2. Receiver V
and V
OD
OC
OH OL
3 V
0 V
Input
1.5 V
1.5 V
C
= 50 pF
L
(see Note B)
R
= 54 Ω
L
t
t
Generator
(see Note A)
dD
dD
Output
50 Ω
≈ 2.5 V
90%
10%
50%
50%
Output
≈ – 2.5 V
t
t
tD
tD
VOLTAGE WAVEFORMS
TEST CIRCUIT
Figure 3. Driver Differential-Output Test Circuit and Voltage Waveforms
Output
3 V
(SN75178B)
S1
Input
1.5 V 1.5 V
0 V or 3 V
(SN75177B)
0 V
0.5 V
t
PZH
C
= 50 pF
L
R
= 110 Ω
L
(see Note B)
SN75178B
V
OH
Generator
(see Note A)
Output
50 Ω
2.3 V
t
Enable is
V
≈ 0 V
off
Active Low
PHZ
VOLTAGE WAVEFORMS
TEST CIRCUIT
Figure 4. Driver Enable and Disable Times
5 V
3 V
0 V
(SN75178B)
Input
1.5 V
1.5 V
R
= 110 Ω
L
S1
(SN75177B)
Output
3 V or 0 V
t
PZL
t
PLZ
5 V
0.5 V
C
= 50 pF
L
(see Note B)
Generator
(see Note A)
SN75178B
Enable is
Active Low
50 Ω
2.3 V
Output
V
OL
VOLTAGE WAVEFORMS
TEST CIRCUIT
Figure 5. Driver Enable and Disable Times
NOTES: A. The input pulse is supplied by a generator having the following characteristics: PRR ≤ 1 MHz, 50% duty cycle, t ≤ 6 ns, t ≤ 6 ns,
r
f
Z
= 50 Ω.
O
L
B. C includes probe and jig capacitance.
2–6
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TI [ TEXAS INSTRUMENTS ]
