MAX13448E Datasheet, PDF (8/14 Pages) Maxim Integrated Products – 80V Fault-Protected Full-Duplex RS-485 Transceiver

±80V Fault-Protected Full-Duplex
RS-485 Transceiver
PIN
1, 8, 13
2
3
4
5
6, 7
9
10
11
12
14
NAME
N.C.
RO
RE
DE
DI
GND
Y
Z
B
A
V_CC
Pin Description
FUNCTION
No Connection. Not internally connected. Connect N.C. to GND or leave it unconnected.
Receiver Output. If receiver is enabled and (A - B) ≥ -50mV, RO = high; if (A - B) ≥ -200mV, RO = low.
Receiver Output Enable. Drive RE low to enable RO; RO is high impedance when RE is high. Drive
RE high and DE low to enter low-power shutdown mode.
Driver Output Enable. Drive DE high to enable the driver outputs. Drive DE low to put the outputs in
high impedance. Drive RE high and DE low to enter low-power shutdown mode.
Driver Input. Drive DI low to force the noninverting output low and the inverting output high. Drive DI
high to force the noninverting output high and the inverting output low.
Ground
Noninverting Driver Output
Inverting Driver Output
Inverting Receiver Input
Noninverting Receiver Input
Positive Supply. V_CC = +3.0V to +5.5V. Bypass V_CC to GND with a 1µF ceramic capacitor as close
to V_CC as possible. Typical V_CC values are at V_CC = +3.3V and V_CC = +5.0V.
Y
V_OD
Z
R_L/2
R_L/2
V_OC
Figure 1. Driver DC Test Load
V_CC
DE
Y
DI
V_O
Z
C_L
R_L
C_L
Figure 2. Driver Timing Test Circuit
V_CC
DI
0
V_CC/2
t_DPLH
t_DPHL
Z
Y
V_O
V_{OD 0}
-V_O
V_O
1/2 V_O
10%
t_LH
V_OD = V (Y) - V (Z)
90%
90%
t_HL
t_SKEW = |t_DPLH - t_DPHL|
Figure 3. Driver Propagation Delays
1/2 V_O
10%
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