SN74CBTD3384CPWRE4

Overview

The SN74CBTD3384CPWRE4 is a high-speed TTL-compatible FET bus switch manufactured by Texas Instruments. It features low ON-state resistance and bidirectional data flow with near-zero propagation delay. The device includes an integrated diode to VCC for level shifting from 5-V inputs down to 3.3-V outputs. It supports partial-power-down mode via Ioff, ensuring isolation during power off. The component operates within a supply voltage range of 4.5 V to 5.5 V and functions across temperatures from -40°C to +85°C. It is housed in a 24-pin TSSOP package.

Feature Summary

• Integrated diode to VCC provides level shifting for 5-V input down to 3.3-V output levels
• Active undershoot-protection circuitry on A and B ports protects against undershoot up to -2 V
• Supports partial-power-down applications using Ioff feature to prevent damaging backflow current
• Bidirectional data flow with low ON-state resistance allowing minimal propagation delay

Applications

• Memory interleaving
• Bus isolation
• Low-distortion signal gating

Procurement Notes

Verify the ordering suffix 'E4' indicates lead-free status and RoHS compliance as per manufacturer documentation. Confirm the PW package designation corresponds to the TSSOP form factor. Ensure the operating temperature range meets system requirements of -40°C to +85°C. Check that the 4.5 V to 5.5 V supply voltage aligns with the target application's power rails. Validate pinout compatibility with existing PCB layouts before finalizing procurement.

Selection Notes

Select this component when bidirectional switching between 5-V and 3.3-V domains is required without external level shifters. The integrated level-shifting diode simplifies design for mixed-voltage systems. Choose this part for applications demanding low distortion and high-speed data transfer. The Ioff feature makes it suitable for systems requiring safe partial-power-down states. Ensure control inputs are compatible with TTL or 5-V/3.3-V CMOS logic levels.

Part Context

This device belongs to the SN74CBT series of high-speed bus switches. It is specifically designed for applications requiring low ON-state resistance and fast switching speeds. The CBTD variant distinguishes itself through the inclusion of level-shifting capabilities and active undershoot protection. It serves as a critical interface component in digital and analog signal routing scenarios.

Replacement Considerations

SN74CBTD3384CDWR

FAQ

How does the device handle undershoot events?

Active undershoot-protection circuitry on the A and B ports 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 integrated diode?

The integrated diode in series with VCC provides level shifting, allowing 5-V input signals to be shifted down to 3.3-V output levels.

How does the Ioff feature benefit the system?

The Ioff feature ensures that damaging current will not backflow through the device when it is powered down, supporting partial-power-down mode operation.