SN74CB3Q16811DGVR

Overview

The SN74CB3Q16811DGVR is a 24-bit FET bus switch from the Texas Instruments Widebus family, housed in a 56-pin TVSOP package. It operates within a supply voltage range of 2.3 V to 3.6 V and supports data I/O levels up to 5.5 V. The device features low on-state resistance (5 Ω typical) and low input/output capacitance (4 pF typical). It includes precharged B-port outputs via a bias voltage pin to minimize signal distortion during live insertion.

Feature Summary

• Supports partial-power-down operation through dedicated Ioff circuitry that prevents damaging current backflow when the device is powered down.
• Features B-port outputs precharged by an external bias voltage to minimize signal distortion during hot plugging and live insertion events.
• Provides bidirectional data flow with near-zero propagation delay and rail-to-rail switching capabilities across the data ports.

Applications

• PCI hot plug applications
• Hot docking systems
• Memory interleaving
• Bus isolation circuits

Procurement Notes

Verify the specific ordering suffix 'DGVR' corresponds to the TVSOP-56 package and tape-and-reel carrier configuration. Confirm the operating temperature range matches the application requirements of -40°C to 85°C. Ensure the design accounts for the 56-pin footprint dimensions provided in the mechanical data section.

Selection Notes

Select this component for high-bandwidth interfaces requiring low capacitive loading and minimal signal distortion. The integrated charge pump ensures flat on-state resistance over the full voltage swing. Verify that the control inputs are compatible with the required logic levels for the target system environment.

Part Context

This part belongs to the SN74CB3Q series of low-voltage FET bus switches. It is functionally equivalent to IDT QS3VH bus switches. The device is organized as two independent 12-bit bus switches or one 24-bit switch, offering flexible configuration options for complex digital bus architectures.

Replacement Considerations

SN74CB3Q16811DLR

FAQ

How does the device handle live insertion noise?

The B-port outputs are precharged to a bias voltage (BIASV), which minimizes glitches caused by parasitic capacitance during card insertion or removal into an active bus.

What is the purpose of the Ioff feature?

The Ioff circuitry supports partial-power-down mode by preventing damaging current backflow through the device when it is powered down but the bus remains active.