SP26LV432 Datasheet, PDF (16/20 Pages) Sipex Corporation – High Speed, Low Power Quad RS-422 Differential Line Receiver

SP26LV432
HIGH SPEED +3.3V QUAD RS-422 DIFFERENTIAL LINE RECEIVER
REV. 1.0.0
1.0 PRODUCT DESCRIPTION
The SP26LV432 is a low-power quad differential line receiver designed for digital data transmission meeting
the specifications of the EIA standard RS-422 serial protocol. The SP26LV432 features Exar's BiCMOS
process allowing low power operational characteristics of CMOS technology while meeting all of the demands
of the RS-422 serial protocol up to 50Mbps under load in harsh environments.
The RS-422 standard is ideal for multi-drop applications and for long-distance communication. The RS-422
protocol allows up to 10 receivers to be connected to a data bus, making it an ideal choice for multi-drop
applications. Since the cabling can be as long as 4,000 feet, RS-422 Receivers have an input sensitivity of
200mV over the wide (-7.0V to +7.0V) common mode range to accommodate ground potential differences.
Internal pull-up and pull-down resistors prevent output oscillation on unused channels. Because the RS-422 is
a differential interface, data is virtually immune to noise in the transmission line.
The SP26LV432 accepts RS-422 levels and translates these into TTL or CMOS output levels. The SP26LV432
features active HIGH and active LOW receiver enable controls common to all four receiver channels see
Table 1. A logic HIGH on the ENABLE pin (pin 4) or a logic LOW on the ENABLE pin (pin 12) will enable the
receiver outputs. A logic LOW on the ENABLE pin (pin 4) and a logic HIGH on the ENABLE pin (pin 12) will
force the receiver outputs into high impedance (high-Z). Refer to the truth table in Table 1.
The RS-422 line receivers feature high source and sink current capability. All receivers are internally protected
against short circuits on their inputs. The receivers feature tri-state outputs with 6mA source and sink
capability. The typical receiver propagation delay is 14ns (35ns max). To minimize reflections, the multipoint
bus transmission line should be terminated at both ends in its characteristic impedance, and stub lenghts off
the main line should be kept as short as possible.
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