SN74CBT3384CDBQR

Overview

The SN74CBT3384CDBQR is a high-speed TTL-compatible FET bus switch manufactured by Texas Instruments. It features active undershoot protection on A and B ports up to -2 V, bidirectional data flow with near-zero propagation delay, and low ON-state resistance (ron = 3 Ω typical). The device operates within a VCC range of 4 V to 5.5 V and supports data I/O levels from 0 V to 5 V. It includes two independent 5-bit bus switches controlled by separate OE inputs, housed in a 24-pin SSOP (QSOP) DBQ package.

Feature Summary

• Active undershoot-protection circuitry ensures proper OFF state during undershoot events up to -2 V
• Supports partial-power-down mode operation via the Ioff feature to prevent backflow current
• Provides bidirectional data flow between A and B ports when enabled

Applications

• PCI interface applications
• Memory interleaving systems
• Bus isolation circuits
• Low-distortion signal gating

Procurement Notes

Verify that the component matches the SN74CBT3384CDBQR designation and the 24-pin SSOP (QSOP) DBQ package configuration. Confirm the operating temperature range aligns with industrial specifications (-40°C to +85°C). Ensure the datasheet revision corresponds to SCDS132A revised October 2003 for accurate electrical characteristics and absolute maximum ratings.

Selection Notes

Select this component when designing systems requiring high-speed switching with minimal signal distortion. The low input/output capacitance minimizes loading effects, making it suitable for sensitive analog or digital signal paths. Verify control input compatibility with TTL or 5-V/3.3-V CMOS outputs to ensure proper logic level interfacing across the entire operating voltage range.

Part Context

This device belongs to the SN74CBT3384C series of high-speed FET bus switches. It is organized as two 5-bit bus switches, allowing flexible configuration as either two 5-bit switches or one 10-bit switch. The series is designed for applications demanding low power consumption and robust latch-up performance exceeding 100 mA per JESD 78, Class II standards.

Replacement Considerations

SN74CBT3384CDWR

FAQ

How does the device handle undershoot events?

The SN74CBT3384CDBQR incorporates active undershoot-protection circuitry on both the A and B ports. This circuitry senses an undershoot event and ensures the switch remains in the correct OFF state, providing protection against undershoot voltages down to -2 V.

What is the function of the Ioff feature?

The Ioff feature allows the device to be fully specified for partial-power-down applications. It ensures that damaging current will not backflow through the device when it is powered down, maintaining isolation during power-off states.