SN74CB3Q3384A_2 Datasheet, PDF (2/15 Pages) Texas Instruments – 10-BIT FET BUS SWITCH 2.5-V/3.3-V LOW-VOLTAGE HIGH-BANDWIDTH BUS SWITCH

SN74CB3Q3384A
10-BIT FET BUS SWITCH
2.5-V/3.3-V LOW-VOLTAGE HIGH-BANDWIDTH BUS SWITCH
SCDS114D – DECEMBER 2002 – REVISED JUNE 2005
www.ti.com
DESCRIPTION/ORDERING INFORMATION (CONTINUED)
The SN74CB3Q3384A is a high-bandwidth FET bus switch utilizing a charge pump to elevate the gate voltage of
the pass transistor, providing a low and flat ON-state resistance (r_on). The low and flat ON-state resistance 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 SN74CB3Q3384A provides an optimized
interface solution ideally suited for broadband communications, networking, and data-intensive computing
systems.
The SN74CB3Q3384A is organized as two 5-bit bus switches with separate output-enable (1OE, 2OE) inputs. It
can be used as two 5-bit bus switches or as one 10-bit bus switch. When OE is low, the associated 5-bit 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 associated 5-bit 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.
INPUT
OE
L
H
FUNCTION TABLE
(EACH 5-BIT BUS SWITCH)
INPUT/OUTPUT
A
B
Z
FUNCTION
A port = B port
Disconnect
LOGIC DIAGRAM (POSITIVE LOGIC)
3
1A1
2
SW
1B1
11
1A5
1
1OE
10
SW
1B5
14
2A1
22
2A5
13
2OE
15
SW
2B1
23
SW
2B5
2