Datasheet

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DESCRIPTION/ORDERING INFORMATION (CONTINUED)
GQN PACKAGE
(TOP VIEW)
1 2 3 4
A
B
C
D
E
SN74CB3Q3245
8-BIT FET BUS SWITCH
2.5-V/3.3-V LOW-VOLTAGE HIGH-BANDWIDTH BUS SWITCH
SCDS124B – JULY 2003 – REVISED MARCH 2005
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.
This device is fully specified for partial-power-down applications using I
off
. The I
off
circuitry prevents damaging
current backflow through the device when it is powered down. The device has isolation during power off.
To ensure the high-impedance state during power up or power down, OE should be tied to V
CC
through a pullup
resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.
ORDERING INFORMATION
T
A
PACKAGE
(1)
ORDERABLE PART NUMBER TOP-SIDE MARKING
QFN – RGY Tape and reel SN74CB3Q3245RGYR BU245
SSOP (QSOP) – DBQ Tape and reel SN74CB3Q3245DBQR CB3Q3245
Tube SN74CB3Q3245PW
–40 ° C to 85 ° C TSSOP – PW BU245
Tape and reel SN74CB3Q3245PWR
TVSOP – DGV Tape and reel SN74CB3Q3245DGVR BU245
VFBGA – GQN Tape and reel SN74CB3Q3245GQNR BU245
(1) Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
TERMINAL ASSIGNMENTS
(1)
1 2 3 4
A A1 NC V
CC
OE
B A3 B2 A2 B1
C A5 A4 B4 B3
D A7 B6 A6 B5
E GND A8 B8 B7
(1) NC - No internal connection
FUNCTION TABLE
INPUT INPUT/OUTPUT
FUNCTION
OE A
L B A port = B port
H Z Disconnect
2