MAX13450E_1011 Datasheet, PDF (9/17 Pages) Maxim Integrated Products – RS-485 Transceivers with Integrated 100Ω/120Ω Termination Resistors

RS-485 Transceivers with Integrated
100Ω/120Ω Termination Resistors
Test Circuits and Waveforms (continued)
VL
DE
0V
V_CC
A/Y, B/Z
VOL
VOH
A/Y, B/Z
0V
Figure 4. Driver Enable and Disable Times
VL/2
V_L/2
t_DZL(SHDN),t_DZL
tDLZ
(VCC + VOL)/2 _{OUTPUT NORMALLY LOW}
V_OH/2
OUTPUT NORMALLY HIGH
tDZH(SHDN),tDZH
tDHZ
VOL + 0.25V
VOH - 0.25V
OUTPUT
UNDER TEST
500Ω
CL
VCC
S1
S2
Figure 5. Driver-Enable and Disable-Timing Test Load
B
ATE
VID
R
RECEIVER
OUTPUT
A
Figure 6. Receiver Propagation Delay Test Circuit
A
B
VROH
RO
VROL
f = 1MHz, tLH ≤ 3ns, tHL ≤ 3ns
1V
-1V
tRPHL
tRPLH
VL/2
V_L/2
t_RSKEW = |t_RPHL - t_RPLH|
Figure 7. Receiver Propagation Delays
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