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SN74CBT3245A
OCTAL FET BUS SWITCH
SCDS002J – NOVEMBER 1992 – REVISED MAY 1998
D
Functionally Equivalent to QS3245
D
Standard ’245-Type Pinout
D
5-Ω Switch Connection Between Two Ports
D
TTL-Compatible Input Levels
D
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB, DBQ), Thin Very Small-Outline (DGV),
and Thin Shrink Small-Outline (PW)
Packages
description
The SN74CBT3245A provides eight bits of
high-speed TTL-compatible bus switching in a
standard ’245 device pinout. The low on-state
resistance of the switch allows connections to be
made with minimal propagation delay.
The device is organized as one 8-bit switch. When output enable (OE
connected to port B. When OE
ports.
The SN74CBT3245A is characterized for operation from –40°C to 85°C.
is high, the switch is open and a high-impedance state exists between the two
FUNCTION TABLE
INPUT
OE
L A port = B port
H Disconnect
DB, DBQ, DGV, DW, OR PW PACKAGE
(TOP VIEW)
20
19
18
17
16
15
14
13
12
11
V
OE
B1
B2
B3
B4
B5
B6
B7
B8
CC
1
NC
2
A1
3
A2
4
A3
5
A4
6
A5
7
A6
8
A7
9
A8
GND
10
NC – No internal connection
) is low, the switch is on and port A is
logic diagram (positive logic)
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.
A1
A8
OE
2
9
19
18
11
B1
B8
Copyright 1998, Texas Instruments Incorporated
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
1
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SN74CBT3245A
OCTAL FET BUS SWITCH
SCDS002J – NOVEMBER 1992 – REVISED MAY 1998
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
Input voltage range, V
–0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CC
(see Note 1) –0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I
†
Continuous channel current 128 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
Package thermal impedance, θ
IK
(V
< 0) –50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I/O
(see Note 2): DB package 115°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
JA
DBQ package 118°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DGV package 146°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DW package 97°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package 128°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output negative-voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51.
–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
stg
recommended operating conditions (see Note 3)
MIN MAX UNIT
V
V
V
T
NOTE 3: All unused control inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Supply voltage 4 5.5 V
CC
High-level control input voltage 2 V
IH
Low-level control input voltage 0.8 V
IL
Operating free-air temperature –40 85 °C
A
Implications of Slow or Floating CMOS Inputs
, literature number SCBA004.
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP‡MAX UNIT
V
IK
I
I
I
CC
§
∆I
C
C
r
‡
All typical values are at VCC = 5 V (unless otherwise noted), TA = 25°C.
§
This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND.
¶
Measured by the voltage drop between the A and B terminals at the indicated current through the switch. On-state resistance is determined by
the lowest voltage of the two (A or B) terminals.
Control inputs VCC = 5.5 V, One input at 3.4 V , Other inputs at VCC or GND 3.5 mA
CC
Control inputs VI = 3 V or 0 4 pF
i
io(OFF)
VCC = 4.5 V, II = –18 mA –1.2 V
VCC = 5.5 V, VI = 5.5 V or GND ±5 µA
VCC = 5.5 V, IO = 0, VI = VCC or GND 50 µA
VO = 3 V or 0, OE = V
VCC = 4 V,
TYP at VCC = 4 V
VCC = 4.5 V
VI = 2.4 V, II = 15 mA
=
I
VI = 2.4 V, II = 15 mA 10 15
CC
II = 64 mA 5 7
II = 30 mA 5 7
4 pF
Ω
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265