Texas Instruments SN74CBT16211CDL

Overview

SN74CBT16211CDL from Texas Instruments is a 24-channel bidirectional FET bus switch IC organized as two independent 12-bit switches, featuring 3 Ω typical ON-state resistance (ron), <0.24 ns propagation delay at 4 V, and −2 V undershoot protection on A/B ports. It operates from 4 V to 5.5 V and supports mixed-voltage signaling (0.8 V to 5 V) in PCI interface and memory interleaving applications.

For engineers reviewing the SN74CBT16211CDL datasheet, SN74CBT16211CDL pinout, SN74CBT16211CDL application, or SN74CBT16211CDL equivalent, key selection criteria include bidirectional low-distortion signal gating, partial-power-down Ioff support, high-speed TTL/CMOS-compatible control inputs, and SSOP-56 package compatibility with industrial temperature range (−40°C to 85°C).

Technical Context

The SN74CBT16211CDL implements dual 12-bit FET-based analog/digital bus switches with separate 1OE and 2OE enable controls. Each switch channel provides near-zero propagation delay via low-impedance MOSFET paths and integrated undershoot-protection circuitry that actively clamps A/B port voltages down to −2 V while maintaining OFF-state isolation.

It features Ioff partial-power-down capability, ensuring no backflow current when VCC = 0 V, and supports 0–5.5 V data I/O signaling across all logic families. Control inputs accept TTL or 3.3/5-V CMOS levels, and input/output capacitance is minimized (Cio(OFF) = 5.5 pF typical) to reduce loading and signal distortion.

Key Specifications

Pinout & Package

SN74CBT16211CDL uses a 56-pin SSOP (Shrink Small-Outline Package) with 0.5-mm pitch, 13.9 mm × 7.9 mm body size, and 1.2 mm max height per JEDEC MO-194. Pin 1 is located at top-left corner with index area marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional bus switch applications.

Compared with SN74CBT16211CDL, SN74CBTD16211DGGR adds bus-hold but increases quiescent current, while 74ALVC164245DGGR sacrifices bidirectionality and speed for wider voltage flexibility-neither is pin-compatible nor functionally interchangeable without design revision.

Availability

SN74CBT16211CDL is available at Aetrix Electronics and suitable for PCI interface design, memory subsystem integration, and mixed-voltage signal routing requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for SN74CBT16211CDL includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with over 90 years of innovation in high-reliability industrial and automotive components.

The SN74CBT16211CDL belongs to TI's Widebus™ family of high-speed bus switches, engineered specifically for low-latency, low-distortion signal routing in computing, communications, and test equipment where timing integrity and voltage interoperability are critical.

FAQ

What is the maximum undershoot voltage the SN74CBT16211CDL can tolerate on its A and B ports?

The SN74CBT16211CDL provides active undershoot protection rated to −2 V on both A and B ports, verified under VCC = 5.5 V with switch OFF. This protection is implemented via internal clamp circuitry that maintains OFF-state isolation even during transient negative excursions, eliminating the need for external Schottky diodes in ruggedized designs. The SN74CBT16211CDL datasheet specifies VIKU = −2 V as the minimum undershoot threshold before clamping activates.

Does the SN74CBT16211CDL support true bidirectional signal flow without direction control pins?

Yes, the SN74CBT16211CDL supports fully bidirectional signal flow on all 24 channels without requiring direction-control signals. Each of its two 12-bit switch banks connects A and B ports through symmetrical FET paths, allowing data to pass in either direction based solely on voltage potential-no DIR pin or internal latching is involved. This architecture is confirmed in the functional table and logic diagram of the SN74CBT16211CDL datasheet.

Can the SN74CBT16211CDL be used in partial-power-down mode, and what is its Ioff specification?

Yes, the SN74CBT16211CDL supports partial-power-down mode via its Ioff feature. When VCC = 0 V, the device limits off-state current to ≤10 µA across all I/O ports, preventing damaging back-current flow from live buses into unpowered sections. This behavior is guaranteed over the full −40°C to 85°C operating range and is explicitly tested per JESD 78 Class II latch-up standards. The SN74CBT16211CDL's Ioff rating ensures safe operation during hot-swap or multi-rail power sequencing.

What package type and dimensions does the SN74CBT16211CDL use, and is it RoHS-compliant?

The SN74CBT16211CDL uses a 56-pin SSOP (DL package) with 0.5-mm pitch, 13.9 mm × 7.9 mm body size, and 1.2 mm maximum height, compliant with JEDEC MO-194. It is RoHS-compliant with NiPdAu (NIPDAU) lead finish and MSL Level-1 rating (260°C peak reflow). The package drawing DLD0056A defines land patterns, stencil apertures, and solder mask openings for reliable assembly. All SN74CBT16211CDL units shipped by Aetrix meet IPC-J-STD-020 moisture sensitivity requirements.

How does the SN74CBT16211CDL handle mixed-voltage signaling between different logic families?

The SN74CBT16211CDL supports 0–5.5 V data I/O signaling across all pins, enabling direct connection between 0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, and 5-V logic families without external level shifters. Its control inputs accept TTL-compatible thresholds (VIH ≥ 2 V, VIL ≤ 0.8 V), allowing drive from both 3.3-V and 5-V CMOS sources. This mixed-voltage capability is validated in the recommended operating conditions table of the SN74CBT16211CDL datasheet.