SN74CBTD3305CPW

Overview

The SN74CBTD3305CPW is a dual FET bus switch in an 8-pin TSSOP package. It operates with a supply voltage (VCC) ranging from 4.5 V to 5.5 V and supports data I/O levels from 0 V to 5.5 V. The device features two independent 1-bit switches with separate output-enable inputs, providing bidirectional data flow. Key electrical parameters include a typical ON-state resistance of 3 Ω at VCC = 5 V, a maximum propagation delay of 0.15 ns at VCC = 5 V, and a typical input/output capacitance of 5 pF when the switch is off.

Feature Summary

• Integrated level shifting capability allows conversion of 5-V input signals down to 3.3-V output levels via an internal diode connected to VCC.
• Active undershoot protection circuitry on A and B ports ensures proper OFF state isolation during signal events up to -2 V.
• Supports partial-power-down mode operation through the Ioff feature, preventing damaging backflow current when the device is unpowered.
• Low input/output capacitance minimizes loading effects and reduces signal distortion for high-speed applications.

Applications

• USB interface circuits
• Memory interleaving systems
• Bus isolation networks
• Low-distortion signal gating

Procurement Notes

Verify that the ordering suffix 'PW' corresponds to the TSSOP-8 package variant. Confirm the operating temperature range is specified as -40°C to +85°C. Ensure control inputs are tied to VCC or GND to maintain proper device operation. Check RoHS compliance status if required by specific manufacturing standards.

Selection Notes

Select this component when interfacing between 5-V and 3.3-V logic domains requiring bidirectional data transfer. The integrated level shifter eliminates external components for voltage translation. Consider the low ON-state resistance for minimal signal attenuation. Verify that the 5.5-V maximum supply voltage aligns with the system power rails.

Part Context

This device belongs to the SN74CBTD3305C family of high-speed TTL-compatible FET bus switches. It is designed for applications requiring near-zero propagation delay and low ON-state resistance. The product line supports both digital and analog signal switching needs within standard 5-V logic environments.

Replacement Considerations

SN74CBTD3305CDR is a tape-and-reel version of the same functional device in a SOIC package. SN74CBTD3305CD is the tube-packaged equivalent in a SOIC package. These variants share identical electrical characteristics but differ in packaging and shipping quantities.

FAQ

How does the device handle undershoot events?

The SN74CBTD3305CPW includes active undershoot-protection circuitry on the A and B ports. This circuitry senses undershoot events and ensures the switch remains in the proper OFF state, providing protection up to -2 V.

What is the function of the Ioff feature?

The Ioff feature supports partial-power-down mode operation. It ensures that damaging current will not backflow through the device when it is powered down, maintaining isolation during power-off states.

Can the switches operate independently?

Yes, the device contains two 1-bit bus switches with separate output-enable inputs (1OE and 2OE). Each switch can be controlled independently to connect or disconnect its respective A and B ports.