SN74CBTK16245DGVR

Overview

The SN74CBTK16245DGVR is a discontinued 16-bit FET bus switch from Texas Instruments, organized as two independent 8-bit low-impedance switches. It operates at a supply voltage (VCC) of 4 V to 5.5 V and features TTL-compatible input levels. The device includes active-clamp undershoot-protection circuitry on the I/Os that clamps undershoots up to –2 V. It supports partial-power-down mode via Ioff circuitry to prevent damaging backflow current when powered down. Latch-up performance exceeds 100 mA per JESD 78, Class II.

Feature Summary

• Provides 16 bits of high-speed bus switching with standard '16245-type pinout compatibility.
• Features an active-clamp undershoot-protection circuit on I/Os to clamp negative transients.
• Supports partial-power-down applications through dedicated Ioff circuitry for output disabling.
• Offers low on-state resistance for minimal propagation delay between connected ports.

Applications

• Partial-power-down system configurations requiring safe disconnection during power loss.
• High-speed data routing in systems utilizing TTL-compatible logic interfaces.
• Bus expansion architectures needing bidirectional signal transmission with low impedance.

Procurement Notes

This component is officially classified as Obsolete by Texas Instruments and is no longer in production. Verification of availability must rely on third-party distributors or surplus markets rather than direct manufacturer supply. Buyers should confirm the specific package variant and revision status carefully, as lead times and authenticity cannot be guaranteed through official channels. Design-in approval is not possible for new products due to discontinuation status.

Selection Notes

Select this part only for maintenance of existing designs where the obsolete status does not trigger immediate redesign requirements. Verify that the 4 V to 5.5 V operating range and TTL input thresholds align with the target system's voltage domains. Ensure the 48-pin TVSOP package fits the PCB footprint constraints. Consider the lack of future supply support when evaluating long-term product lifecycle risks.

Part Context

The SN74CBTK16245 belongs to the Widebus family of bus switches from Texas Instruments. It utilizes a standard '16245-type pinout to facilitate drop-in replacements in legacy designs. The DGVR suffix indicates the TVSOP-48 package configuration. This specific device integrates FET-based switching technology optimized for low on-resistance and high-speed operation within the 5 V logic family.

Replacement Considerations

Public confirmed substitute part numbers include SN74CBT16245CDGGR.

FAQ

How does the device handle undershoot conditions?

The SN74CBTK16245DGVR incorporates an active-clamp undershoot-protection circuit on its I/Os. This circuit enables current from VCC to clamp undershoots up to –2 V, preventing the pass transistor from turning on unintentionally during negative voltage transients.

What is the function of the Ioff circuitry?

The Ioff circuitry disables the outputs when the device is powered down. This feature prevents damaging current backflow through the device, making it fully specified for partial-power-down applications.