Anything-to-LVDS Dual 2 x 2

Crosspoint Switches

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9

Detailed Description

The LVDS interface standard provides a signaling

method for point-to-point communication over a con-

trolled-impedance medium as defined by the ANSI

TIA/EIA-644 standard. LVDS utilizes a lower voltage

swing than other communication standards, achieving

higher data rates with reduced power consumption,

while reducing EMI emissions and system susceptibility

to noise.

The MAX9392/MAX9393 1.5GHz dual 2 x 2 crosspoint

switches optimize high-speed, low-power, point-to-

point interfaces. The MAX9392 accepts LVDS and

HSTL signals, while the MAX9393 accepts LVPECL and

CML signals. Both devices route the input signals to

either or both LVDS outputs.

When configured as a 1:2 splitter, the outputs repeat

the selected inputs. This configuration creates copies

of signals for protection switching. When configured as

a repeater, the device operates as a two-channel

buffer. Repeating restores signal amplitude, allowing

isolation of media segments or longer media drive.

When configured as a 2:1 mux, select primary or back-

up signals to provide a protection-switched, fault-toler-

ant application.

Input Fail-Safe

The differential inputs of the MAX9392/MAX9393 pos-

sess internal fail-safe protection. Fail-safe circuitry

forces the outputs to a differential low condition for

undriven inputs or when the common-mode voltage

exceeds the specified range. The MAX9392 provides

high-level input fail-safe detection for LVDS, HSTL, and

other GND-referenced differential inputs. The MAX9393

provides low-level input fail-safe detection for LVPECL,

Select Function

The _SEL_ logic inputs control the input and output sig-

nal connections. Two logic inputs control the signal rout-

ing for each channel. _SEL0 and _SEL1 allow the

devices to be configured as a differential crosspoint

switch, 2:1 mux, dual repeater, or 1:2 splitter (Figure 7).

See Table 1 for mode-selection settings (insert A or B for

the _). Channels A and B possess separate select

inputs, allowing different configurations for each channel.

Enable Function

The EN_ _ logic inputs enable and disable each set of

the OUT_0/OUT_0 differential output pair. Connect

EN_0 to GND to disable the OUT_0/OUT_0 differential

output pair. The differential output pairs assert to a dif-

ferential low condition when disabled.

(1:2 SPLITTER CONFIGURATION).

Figure 6. Output Channel-to-Channel Skew

OUT_0

OUT_0 OR OUT_1

OUT_1

2 x 2 CROSSPOINT

2:1 MUX

1:2 SPLITTER

DUAL REPEATER

OUT_0

OUT_1

OUT_0

OUT_1

IN_0

IN_1

IN_0

IN_1

IN_0

IN_1

IN_0 OR IN_1

Figure 7. Programmable Configurations