Half-Duplex RS-485-/RS-422-Compatible
Transceiver with AutoDirection Control
Test Circuits and Waveforms (continued)
V
CC
1.5V
SHDN
0
t
DZL(SHDN)
A, B
V
500Ω
CC
2.3V
S
S
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
OUTPUT
UNDER TEST
1
2
V
OL
C
L
A, B
0
2.3V
t
DZH(SHDN)
Figure 4. Driver Enable and Disable Times
B
RECEIVER
OUTPUT
V
ID
R
ATE
A
Figure 5. Receiver-Propagation-Delay Test Circuit
f = 1MHz, t ≤ 3ns, t ≤ 3ns
LH
HL
1V
A
B
-1V
t
t
RPLH
RPHL
V
OH
RO
1.5V
1.5V
V
OL
t
=
t
- t
RSKEW | RPHL RPLH |
Figure 6. Receiver Propagation Delays
_______________________________________________________________________________________
9