SN75LBC777 Datasheet, PDF (1/14 Pages) Texas Instruments – SINGLE CHIP GEOPORTE/AppleTalkE TRANSCEIVER

SN75LBC777
SINGLE CHIP GEOPORT™/AppleTalk™ TRANSCEIVER
D Single-Chip Interface Solution for the 9-Pin
GeoPort™ Peripheral Data Circuit-
Terminating Equipment (DCE) for the
Intelligent Network Port
D Designed to Operate up to 4-Mbits/s Full
Duplex
D Single 5-V Supply Operation
D 10-kV ESD Protection on Bus Terminals
D Backward Compatible with AppleTalk™ and
LocalTalk™ LANs
D Combines Multiple Components into a
Single Chip Solution
D Complements the SN75LBC776 9-Terminal
GeoPort Host Data Terminal Equipment
(DTE) Interface Device
D LinBiCMOS™ Process Technology
description
The SN75LBC777 is a low-power LinBiCMOS
device that incorporate the drivers and receivers
for a 9-pin GeoPort peripheral 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
SN75LBC777 provides point-to-point connec-
tions between GeoPort-compatible devices with
data transmission rates up to 4-Mbit/s full duplex
over a 4-foot cable. Applications include connec-
tion to telephone, integrated services digital
network (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 LANs.
While the SN75LBC777 is powered off (V_CC = 0)
the outputs are in a high-impedance state. When
the shutdown (SHDN) terminal is high, the charge
pump is powered down and the outputs are in a
high-impedance state. When high, the driver
enable (DEN) terminal puts the outputs of the
differential driver into a high-impedance state.
DA1
V_EE
C–
C+
SHDN
DZ2
DY2
GND
DEN
DA2
SLLS227 – SEPTEMBER 1996
DW PACKAGE
(TOP VIEW)
1
20
GND
2
19
V_CC
3
18
DY1
4
17
DY3
5
16
DA3
6
15
RB2
7
14
RY2
8
13
RB1
9
12
RA1
10
11
RY1
logic diagram (positive logic)
DA2 ¹⁰
DEN ⁹
RY1 ¹¹
DA1
1
DA3 ¹⁶
7 _DY2
6
DZ2
12 _RA1
13 _RB1
18 _DY1
17 _DY3
RY2 ¹⁴
5
SHDN
19
VCC
8
GND
15 _RB2
Charge Pump
2
VEE
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.
Copyright © 1996, Texas Instruments Incorporated
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
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