MAX14840E Datasheet, PDF (5/15 Pages) Maxim Integrated Products – 40Mbps, +3.3V, RS-485 Half-Duplex Transceivers

40Mbps, +3.3V, RS-485 Half-Duplex
Transceivers
Test and Timing Diagrams
A
VOD
B
RL
2
RL
2
V_OC
VCC
DE
DI
A
VOD
B
RL
CL
Figure 1. Driver DC Test Load
Figure 2. Driver Timing Test Circuit
VCC
f = 1MHz, tLH = 3ns, tHL = 3ns
1.5V
1.5V
0
tDPLH
B
t_DPHL
A
VO
VOD 0
-VO
VOD
90%
10%
tLH
Figure 3. Driver Propagation Delays
VOD = [VA - VB]
90%
tDSKEW = tDPLH - tDPHL
10%
tHL
A
GND OR VCC ^DI _D
B
DE
S1
CL
50pF
GENERATOR
50I
OUT
RL = 110I
DE
OUT
tDZH, tDZH(SHDN)
1.5V
VCC
1.5V
0
0.25V
VOH
tDHZ
0
Figure 4. Driver Enable and Disable Times (tDZH, tDHZ)
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