Texas Instruments SN74CBT16212CDL

Overview

SN74CBT16212CDL from Texas Instruments is a 24-bit, high-speed FET bus-exchange switch with bidirectional data flow, 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 SN74CBT16212CDL datasheet, SN74CBT16212CDL pinout, SN74CBT16212CDL application, or SN74CBT16212CDL equivalent, key selection criteria include its 56-pin SSOP (DL) package, Ioff partial-power-down capability, ±128 mA switch current rating, and 8 pF OFF-state I/O capacitance for low-signal-distortion bus isolation.

Technical Context

The SN74CBT16212CDL implements a 12-bit dual-port bus-exchange architecture controlled by three select inputs (S0–S2), enabling eight configurable data-path modes including A1↔B1, A1↔B2, A2↔B1, A2↔B2, and full disconnect. Each of its 24 bidirectional switch channels uses FET-based topology with integrated undershoot-protection circuitry that clamps input transients down to −2 V while maintaining OFF-state integrity.

It features TTL-compatible control inputs (VIH = 2 V min, VIL = 0.8 V max), supports 0–5.5 V data I/O voltage range independent of VCC, and guarantees Ioff leakage ≤10 µA during power-down to prevent backflow. The device meets JESD 78 Class II latch-up immunity (>100 mA) and JESD 22 ESD ratings (2000-V HBM, 1000-V CDM).

Key Specifications

Pinout & Package

SN74CBT16212CDL is housed in a 56-pin Shrink Small-Outline Package (SSOP-DL), 13.9 mm × 7.4 mm body size, 0.5 mm pitch, with exposed metal thermal pad not electrically connected. Pin 1 is located at top-left corner marked by index notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT16212CDGGR and SN74CBT16212CDGVR, the SN74CBT16212CDL provides superior thermal dissipation (56°C/W) and mechanical robustness for hand-soldering or high-reliability industrial deployment, while retaining identical switching performance and undershoot protection.

Availability

SN74CBT16212CDL is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving architectures, and bus isolation systems requiring stable component supply, long-term manufacturability, and guaranteed SSOP packaging.

Supply support for SN74CBT16212CDL 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 logic solutions, with decades of expertise in high-speed interface ICs and bus infrastructure components.

The SN74CBT16212CDL belongs to TI's Widebus™ family of FET bus switches, engineered specifically for low-distortion, high-bandwidth signal routing in computing, communications, and industrial control systems.

FAQ

What is the maximum undershoot voltage the SN74CBT16212CDL can withstand on its A and B ports?

The SN74CBT16212CDL provides active undershoot protection rated to −2 V on both A and B ports, verified per datasheet Figure 2 and absolute maximum ratings. This clamping behavior is implemented via internal circuitry and does not require external components. The SN74CBT16212CDL maintains OFF-state integrity even during −2 V transients, preventing false switching or latch-up in noisy environments such as PCI hot-plug or relay-driven bus systems.

Does the SN74CBT16212CDL support mixed-voltage operation between different logic families?

Yes, the SN74CBT16212CDL supports 0–5.5 V data I/O signaling across all 24 bidirectional channels, enabling interoperability 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 level shifters. Its control inputs accept TTL or 3.3-V/5-V CMOS levels (VIH ≥ 2 V, VIL ≤ 0.8 V), and the SN74CBT16212CDL maintains valid switching thresholds regardless of VCC within 4–5.5 V. This makes it ideal for heterogeneous voltage domain bridging.

What is the thermal performance of the SN74CBT16212CDL in its SSOP-DL package?

The SN74CBT16212CDL in SSOP-DL package has a junction-to-ambient thermal impedance (θJA) of 56°C/W, as specified in the Absolute Maximum Ratings table. This value assumes standard JEDEC 2-layer board conditions and enables reliable operation at full load (±128 mA per channel) up to +85°C ambient. The dual VCC and quad GND pins, along with the 13.9 mm × 7.4 mm body, contribute to this thermal performance-superior to TSSOP (64°C/W) and TVSOP (48°C/W) variants for power-dense layouts.

How does the Ioff feature of the SN74CBT16212CDL protect system-level power domains?

The Ioff feature of the SN74CBT16212CDL limits leakage current to ≤10 µA when VCC = 0 V, preventing damaging back-current flow from powered I/O lines into unpowered sections of the system. This enables safe partial-power-down operation-for example, powering down a memory controller while keeping DRAM banks active. The SN74CBT16212CDL achieves this via internal transistor biasing that disables conduction paths, and it complies with JESD 78 Class II latch-up immunity (>100 mA), ensuring robustness during power sequencing.

Can the SN74CBT16212CDL be used in analog signal routing applications?

Yes, the SN74CBT16212CDL is qualified for analog signal routing due to its low 3 Ω typical ON-state resistance, 8 pF OFF-state I/O capacitance, and flat ron vs. voltage curve across 0–5.5 V. Its bidirectional FET architecture introduces negligible THD or crosstalk, and the SN74CBT16212CDL has been deployed in low-distortion signal gating for sensor multiplexing and audio path switching. However, it is not specified for RF or precision op-amp feedback paths where sub-ohm ron or femtofarad capacitance is required.