SN75LBC978_09 Datasheet, PDF (1/19 Pages) Texas Instruments – 9-CHANNEL DIFFERENTIAL TRANSCEIVER

SN75LBC978
9ĆCHANNEL DIFFERENTIAL TRANSCEIVER
SLLS134F − APRIL 1992 − REVISED APRIL 2005
D Nine Differential Channels for the Data and
Control Paths of the Differential Small
Computer Systems Interface (SCSI)
D Meets or Exceeds the Requirements of
ANSI Standard RS-485 and ISO
8482:1987(E)
D Packaged in Shrink Small-Outline Package
With 25-mil Terminal Pitch
D Designed to Operate at 10 Million Transfers
Per Second
D Low Disabled Supply Current
1.4 mA Typ
D Thermal Shutdown Protection
D Power-Up/Power-Down Glitch Protection
D Positive and Negative Output-Current
Limiting
D Open-Circuit Fail-Safe Receiver Design
description
The SN75LBC978 is a nine-channel differential
transceiver based on the 75LBC176 LinASIC
cell. Use of TI’s LinBiCMOS^† process technolo-
gy allows the power reduction necessary to
integrate nine differential balanced transceivers^†.
On-chip enabling logic makes this device
applicable for the data path (eight data bits plus
parity) and the control path (nine bits) for the Small
Computer Systems Interface (SCSI) standard.
The WRAP function allows in-circuit testing and
wired-OR channels for the BSY, RST, and SEL
signals of the SCSI bus.
The SN75LBC978 is packaged in a shrink
small-outline package (DL) with improved thermal
characteristics using heat-sink terminals. This
package is ideal for low-profile, space-restricted
applications such as hard disk drives.
DL PACKAGE
(TOP VIEW)
NC 1
WRAP2 2
WRAP1 3
1A 4
1DE/RE 5
2A 6
2DE/RE 7
3A 8
3DE/RE 9
4A 10
4DE/RE 11
V_CC ¹²
GND ¹³
GND ¹⁴
GND ¹⁵
GND ¹⁶
GND ¹⁷
V_CC ¹⁸
5A ¹⁹
5DE/RE ²⁰
6A ²¹
6DE/RE ²²
7A ²³
7DE/RE ²⁴
8A ²⁵
8DE/RE ²⁶
9A ²⁷
9DE/RE ²⁸
56 NC
55 NC
54 CE
53 9B +
52 9B −
51 8B +
50 8B −
49 7B +
48 7B −
47 6B +
46 6B −
45 _VCC
44 _GND
43 _GND
42 _GND
41 _GND
40 _GND
39 _VCC
38 _{5B +}
37 _{5B −}
36 _{4B +}
35 _{4B −}
34 _{3B +}
33 _{3B −}
32 _{2B +}
31 _{2B −}
30 _{1B +}
29 _{1B −}
Pins 13 through 17 and 40 through 44 are
connected together to the package lead
frame and signal ground.
The switching speed of the SN75LBC978 is sufficient to transfer data over the data bus at 10 million transfers
per second. Each of the nine identical channels conforms to the requirements of the ANSI RS-485 and
ISO 8482:1987(E) standards referenced by ANSI X3.131-1993 (SCSI-2) and the proposed SCSI-3 standards.
The SN75LBC978 is characterized for operation from 0°C to 70°C.
† _{Patent Pending}
LinASIC and LinBiCMOS are trademarks 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.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Copyright  1997, Texas Instruments Incorporated
1