MAX13174E Datasheet, PDF (6/13 Pages) Maxim Integrated Products – +5V Multiprotocol, Pin-Selectable Cable Terminator

+5V Multiprotocol, Pin-Selectable
Cable Terminator
A
I
AMMETER
V_DM = ±2V
R1 = 52Ω
S1 ON
R3 = 127Ω
S2 OFF
R2 = 52Ω
B
V_CM = ±7V OR ±2V
R_DM
=
V_DM
I
AMMETER
I
V_CM = ±2V
R_CM
=
V_CM
I
A
R1 = 52Ω
S1 ON
R3 = 127Ω
S2 ON
R2 = 52Ω
B
Figure 1. V.11 or V.35 Differential Impedance Measurement
Figure 2. V.35 Common-Mode Impedance Measurement
1 _M0
24 _M1
MAX13174E
23 _M2
22 _DCE/DTE
21 _LATCH
V_CC V_EE
14 2
3 8 11 12 13
1 2 34 5 6
5 4 6 7 9 10 16 15 18 17 19 20
Figure 3. Block Diagram
The state of the MAX13174E’s mode-select pins—M0,
M1, M2, and DCE/DTE—determines the mode of each of
the six termination networks. Table 1 shows a cross-refer-
ence of termination mode and select pin state for each of
the six termination networks within the MAX13174E.
No-Cable Mode
The MAX13174E enters no-cable mode when the mode-
select inputs—M0, M1, and M2—are connected high. In
no-cable mode, all six termination networks are placed
in V.11 mode, with S1 closed and S2 open (Figure 4).
Applications Information
Older multiprotocol interface termination circuits have
been constructed using expensive relays with discrete
resistors, custom cables with built-in termination, or
complex circuit-board configurations to route signals to
the correct termination. The MAX13174E provides a
simple solution to this termination problem. All required
termination configurations are easily cable- or pin-
selectable using the four mode-control input pins (M0,
M1, M2, and DCE/DTE).
Using the MAX13174E in a Multiprotocol
Serial Interface
The MAX13174E terminator is designed to form a com-
plete +5V cable- or pin-selectable multiprotocol
DCE/DTE interface port when used with the
MAX13170E/MAX13172E differential drivers/receivers.
The MAX13174E terminator is designed to use the V_EE
power generated by the MAX13171E’s charge pump
and meets all data sheet specifications when connect-
ed as illustrated in Figure 5. The mode-selection tables
of all three devices are identical, allowing the M0, M1,
M2, and DCE/DTE pins of each device to be connected
to a single 4-wire control bus. The MAX13170E and
MAX13172E provide internal pullups for the four lines,
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