English
Language : 

SN74CBT34X245 Datasheet, PDF (1/7 Pages) Texas Instruments – 32-BIT FET BUS SWITCH
D Member of Texas Instruments’ Widebus +
Family
D 5-Ω Switch Connection Between Two Ports
D TTL-Compatible Input Levels
D Flow-Through Architecture Optimizes PCB
Layout
D Ioff Supports Partial-Power-Down Mode
Operation
D Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
D ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
description
The SN74CBT34X245 provides 32 bits of
high-speed TTL-compatible bus switching. The
low on-state resistance of the switch allows
connections to be made with minimal propagation
delay.
The device is organized as four 8-bit bus switches,
two 16-bit bus switches, or one 32-bit bus switch.
When output enable (OE) is low, the switch is on,
and port A is connected to port B. When OE is
high, the switch is open, and the high-impedance
state exists between the two ports.
This device is fully specified for partial-power-
down applications using Ioff. The Ioff circuitry
disables the outputs, preventing damaging
current backflow through the device when it is
powered down.
SN74CBT34X245
32-BIT FET BUS SWITCH
SCDS089C – MAY 1999 – REVISED MAY 2001
DBB PACKAGE
(TOP VIEW)
NC 1
1A1 2
1A2 3
1A3 4
1A4 5
1A5 6
1A6 7
1A7 8
1A8 9
GND 10
NC 11
2A1 12
2A2 13
2A3 14
2A4 15
2A5 16
2A6 17
2A7 18
2A8 19
GND 20
NC 21
3A1 22
3A2 23
3A3 24
3A4 25
3A5 26
3A6 27
3A7 28
3A8 29
GND 30
NC 31
4A1 32
4A2 33
4A3 34
4A4 35
4A5 36
4A6 37
4A7 38
4A8 39
GND 40
80 VCC
79 1OE
78 1B1
77 1B2
76 1B3
75 1B4
74 1B5
73 1B6
72 1B7
71 1B8
70 VCC
69 2OE
68 2B1
67 2B2
66 2B3
65 2B4
64 2B5
63 2B6
62 2B7
61 2B8
60 VCC
59 3OE
58 3B1
57 3B2
56 3B3
55 3B4
54 3B5
53 3B6
52 3B7
51 3B8
50 VCC
49 4OE
48 4B1
47 4B2
46 4B3
45 4B4
44 4B5
43 4B6
42 4B7
41 4B8
NC – No internal connection
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.
Widebus+ is a trademark of Texas Instruments.
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  2001, Texas Instruments Incorporated
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
1