SN75976A_06 Datasheet, PDF (1/33 Pages) Texas Instruments – 9-CHANNEL DIFFERENTIAL TRANSCEIVER

SN75976A, SN55976A
9-CHANNEL DIFFERENTIAL TRANSCEIVER
SLLS218B – MAY 1995 – REVISED MAY 1997
D Improved Speed and Package Replacement
for the SN75LBC976
D Designed to Operate at up to 20 Million
SN75976A DGG or DL
SN55976A WD
(TOP VIEW)
Data Transfers per Second (Fast-20 SCSI)
D Nine Differential Channels for the Data and
Control Paths of the Small Computer
Systems Interface (SCSI) and Intelligent
Peripheral Interface (IPI)
D SN75976A Packaged in Shrink
Small-Outline Package with 25-Mil Terminal
Pitch (DL) and Thin Shrink Small-Outline
Package with 20-Mil Terminal Pitch (DGG)
D SN55976A Packaged in a 56-Pin Ceramic
Flat Pack (WD)
D Two Skew Limits Available
D ESD Protection on Bus Terminals
Exceeds 12 kV
D Low Disabled Supply Current 8 mA Typ
D Thermal Shutdown Protection
D Positive- and Negative-Current Limiting
D Power-Up/Down Glitch Protection
GND ₁
BSR ₂
CRE 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
56 ^CDE2
55 ^CDE1
54 ^CDE0
53 9B+
52 9B–
51 8B+
50 8B –
49 7B+
48 7B –
47 6B+
46 6B –
45 V_CC
44 GND
43 GND
42 GND
41 GND
40 GND
39 V_CC
38 5B+
5DE/RE 20 37 5B –
description
6A 21 36 4B+
The SN75976A is an improved replacement for
the industry’s first 9-channel RS-485
transceiver — the SN75LBC976. The A version
offers improved switching performance, a smaller
package, and higher ESD protection. The
SN75976A is offered in two versions. The ’976A2
skew limits of 4 ns for the differential drivers and
6DE/RE 22
7A 23
7DE/RE ²⁴
8A ²⁵
8DE/RE ²⁶
9A ²⁷
9DE/RE ²⁸
35 4B –
34 3B+
33 3B –
32 _2B+
31 _{2B –}
30 _1B+
29 _{1B –}
5 ns for the differential receivers complies with the
recommended skew budget of the Fast-20 SCSI
standard for data transfer rates up to 20 million
transfers per second. The ’976A1 supports the
Terminals 13 through 17 and 40 through 44 are
connected together to the package lead frame
and signal ground.
Fast SCSI skew budget for 10 million
transfers per second. The skew limit ensures that the propagation delay times, not only from channel-to-channel
but from device-to-device, are closely matched for the tight skew budgets associated with high-speed parallel
data buses.
The patented thermal enhancements made to the 56-pin shrink small-outline package (SSOP) of the SN75976
have been applied to the new, thin shrink, small-outline package (TSSOP). The TSSOP package offers even
less board area requirements than the SSOP while reducing the package height to 1 mm. This provides more
board area and allows component mounting to both sides of the printed circuit boards for low-profile,
space-restricted applications such as small form-factor hard disk drives.
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.
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