SN74CBT6800CDW

Overview

The SN74CBT6800CDW is a 10-bit TTL-compatible FET bus switch in a 24-pin SOIC (DW) package. It operates within a VCC range of 4 V to 5.5 V and supports data I/O levels from 0 V to 5.5 V, including 0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, and 5-V signaling. The device features low ON-state resistance with typical values of 3 Ω at VI=0 and 8 Ω at VI=2.4 V. Propagation delay is specified as 0.15 ns to 0.24 ns. Control inputs are compatible with TTL or 5-V/3.3-V CMOS outputs.

Feature Summary

• Active undershoot protection on A and B ports prevents signal distortion during off-isolation events down to -2 V.
• B-port precharging via the BIASV pin minimizes live-insertion noise and glitching effects during hot-plugging.
• Ioff feature ensures partial-power-down mode operation by preventing damaging backflow current when VCC is zero.
• Bidirectional data flow capability with near-zero propagation delay for high-speed digital and analog applications.

Applications

• PCI interface bus switching
• Memory interleaving
• Bus isolation
• Low-distortion signal gating

Procurement Notes

Verify the specific ordering suffix 'DW' corresponds to the SOIC-24 tube packaging configuration. Confirm that the component meets RoHS compliance standards and check the latest product life cycle status to ensure availability for production. Ensure design compatibility with the required operating temperature range of -40°C to +85°C.

Selection Notes

Select this component for designs requiring 10-bit bidirectional switching with minimal signal degradation. The device is suitable for systems utilizing 5-V logic families where low capacitance and fast switching speeds are critical. Ensure the BIASV pin is properly biased to match receiver input thresholds if live insertion is anticipated.

Part Context

This part belongs to the Widebus family of high-speed bus switches manufactured by Texas Instruments. It is designed to provide robust signal integrity in complex digital systems. The SN74CBT6800C variant specifically integrates active protection circuits to handle voltage transients and undershoot conditions common in high-density bus architectures.

Replacement Considerations

SN74CBT6800CDWR

FAQ

How does the device handle live insertion?

The B port is precharged to the user-selectable bias voltage (BIASV) through an equivalent 10-kΩ resistor when OFF. This minimizes live-insertion noise by ensuring glitches do not cross the input threshold region of receivers.

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 (VCC = 0 V), providing isolation during power-off states.