Undershoot Protection for Off-Isolation on

A and B Ports Up To −2 V

Integrated Diode to VCC Provides 5-V Input

Down To 3.3-V Output Level Shift

Bidirectional Data Flow, With Near-Zero

Propagation Delay

Low ON-State Resistance (ron)

Characteristics (ron = 3 Ω Typical)

Low Input/Output Capacitance Minimizes

Loading and Signal Distortion

(Cio(OFF) = 5 pF Typical)

Data and Control Inputs Provide

Undershoot Clamp Diodes

VCC Operating Range From 4.5 V to 5.5 V

Data I/Os Support 0 to 5-V Signaling Levels

(0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, 5-V)

Control Inputs Can be Driven by TTL or

5-V/3.3-V CMOS Outputs

Ioff Supports Partial-Power-Down Mode

Operation

Latch-Up Performance Exceeds 100 mA Per

JESD 78, Class II

ESD Performance Tested Per JESD 22

− 2000-V Human-Body Model

(A114-B, Class II)

− 1000-V Charged-Device Model (C101)

Supports Both Digital and Analog

Applications: USB Interface, Memory

Interleaving, Bus Isolation, Low-Distortion

Signal Gating

description/ordering information

The SN74CBTD3305C is a high-speed TTL-compatible FET bus switch with low ON-state resistance (ron),

allowing for minimal propagation delay. This device features an integrated diode in series with VCC to provide

level shifting for 5-V input down to 3.3-V output levels. Active Undershoot-Protection Circuitry on the A and B

ports of the SN74CBTD3305C provides protection for undershoot up to −2 V by sensing an undershoot event

and ensuring that the switch remains in the proper OFF state.

The SN74CBTD3305C is organized as two 1-bit bus switches with separate output-enable (1OE, 2OE) inputs.

It can be used as two 1-bit bus switches or as one 2-bit bus switch. When OE is high, the associated 1-bit bus

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

OE is low, the associated 1-bit bus switch is OFF, and a high-impedance state exists between the A and B ports.