MAX13450E_1011 Datasheet, PDF (10/17 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
RE
0V
V_L
RO
VROL
VROH
RO
0V
DI = 0V
VL/2
V_L/2
tRZL(SHDN), tRZL
tRHZ
(VL + VROL)/2 _{OUTPUT NORMALLY LOW}
V_ROH/2
OUTPUT NORMALLY HIGH
t_RZH(SHDN), t_RZH
tRHZ
Figure 8. Receiver Enable and Disable Times
R_OH + 0.25V
R_OH - 0.25V
500Ω
RO
CL
Figure 9. Receiver Enable and Disable Times
VCC
S1
S2
IA = VAB/RD
A
RO
RECEIVER
B
TERM
Figure 10. Termination Resistor Turn-On/-Off Times
VL
TERM
0V
IA
VAB = VA - VB
RD = R100 OR R200
VL/2
t_REN
90%
tREN
10%
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