SN74CB3Q3245

8BIT FET BUS SWITCH

2.5V/3.3V LOW VOLTAGE HIGHBANDWIDTH BUS SWITCH

SCDS124B − JULY 2003 − REVISED NOVEMBER 2003

2

POST OFFICE BOX 655303

description/ordering information

The SN74CB3Q3245 is a high-bandwidth FET bus switch utilizing a charge pump to elevate the gate voltage

allows for minimal propagation delay and supports rail-to-rail switching on the data input/output (I/O) ports. The

device also features low data I/O capacitance to minimize capacitive loading and signal distortion on the data

bus. Specifically designed to support high-bandwidth applications, the SN74CB3Q3245 provides an optimized

interface solution ideally suited for broadband communications, networking, and data-intensive computing

systems.

The SN74CB3Q3245 is organized as an 8-bit bus switch with a single output-enable (OE) input. When OE is

low, the bus switch is ON and the A port is connected to the B port, allowing bidirectional data flow between ports.

When OE is high, the bus switch is OFF and a high-impedance state exists between the A and B ports.

current backflow through the device when it is powered down. The device has isolation during power off.

resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

ORDERING INFORMATION

TA

PACKAGE†

ORDERABLE

PART NUMBER

TOP-SIDE

MARKING

QFN − RGY

Tape and reel

SN74CB3Q3245RGYR

BU245

SSOP (QSOP) − DBQ

Tape and reel

SN74CB3Q3245DBQR

CB3Q3245

−40

°C to 85°C

TSSOP − PW

Tube

SN74CB3Q3245PW

BU245

−40

°C to 85°C

TSSOP − PW

Tape and reel

SN74CB3Q3245PWR

BU245

TVSOP − DGV

Tape and reel

SN74CB3Q3245DGVR

BU245

VFBGA − GQN

Tape and reel

SN74CB3Q3245GQNR

BU245

† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are

available at www.ti.com/sc/package.

terminal assignments

1234

A

A1

NC

VCC

OE

B

A3

B2

A2

B1

C

A5

A4

B4

B3

D

A7

B6

A6

B5

E

GND

A8

B8

B7

NC − No internal connection

FUNCTION TABLE

INPUT

INPUT/OUTPUT

FUNCTION

INPUT

OE

INPUT/OUTPUT

A

FUNCTION

L

B

A port = B port

H

Z

Disconnect

GQN PACKAGE

(TOP VIEW)

1

234

A

B

C

D

E