D Supports a 9-Pin GeoPort™ Host Interface
Standard for the Intelligent Network Port
D Designed to Operate up to 4-Mbit/s Full
D ± 5 V Supply Operation
D Has Driver Short-Circuit Protection
D Includes Failsafe Mechanism for Open
D Is Backward Compatible with AppleTalk™
D Combines Multiple Components into a
Single Chip Solution
D Complements the SN75LBC772 9-Pin
GeoPort Peripheral (DCE) Interface Device
D Uses LinBiCMOS™ Process Technology
SLLS247C – FEBRUARY 1997 – NOVEMBER 1997
logic diagram (positive logic)
The SN75LBC773 is a low-power LinBiCMOS
device that incorporates the drivers and receivers
for a 9-pin GeoPort host interface. GeoPort
combines hybrid EIA/TIA-422-B and EIA/
TIA-423-B drivers and receivers to transmit data
up to four-Mbit/s full duplex. GeoPort is a serial
communications standard that is intended to
replace the RS-232, AppleTalk, and printer ports
all in one connector in addition to providing
real-time data transfer capability. The
SN75LBC773 provides point-to-point connec-
tions between GeoPort-compatible devices with
data transmission rates up to 4-Mbit/s full duplex
featuring a hot-plug capability. Applications
include connection to telephone, ISDN, digital
sound and imaging, fax-data modems, and other
traditional serial and parallel connections. The
GeoPort is backwardly compatible to both
LocalTalk and AppleTalk.
While the SN75LBC773 is powered off (VCC and VEE = 0 ), the outputs are in a high-impedance state. A logic
high on the driver enable (DEN) or logic low on the receive enable (REN) terminals places the outputs of the
differential driver and receivers, respectively, into a high-impedance state. All drivers and receivers have
fail-safe mechanisms that ensure a high output state when the inputs are left open.
The SN75LBC773 is characterized for operation over the 0°C to 70°C temperature range.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
GeoPort, LocalTalk, and AppleTalk are trademarks of Apple Computer, Incorporated.
LinBiCMOS is a trademark of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright © 1997, Texas Instruments Incorporated