Texas Instruments SN74CBT16212CDGGR

Overview

SN74CBT16212CDGGR from Texas Instruments is a 24-bit FET bus-exchange switch with bidirectional signal routing, 3 Ω typical ON-state resistance, <0.24 ns propagation delay at 4 V, and −2 V undershoot protection on A/B ports. It enables dynamic bus reconfiguration in PCI interface and memory interleaving systems.

For engineers reviewing the SN74CBT16212CDGGR datasheet, SN74CBT16212CDGGR pinout, SN74CBT16212CDGGR application, or SN74CBT16212CDGGR equivalent, key selection criteria include its 56-pin TSSOP package, Ioff partial-power-down support, 0–5-V data signaling compatibility, and select-input-controlled 12-bit exchange modes (S0/S1/S2).

Technical Context

The SN74CBT16212CDGGR implements a dual 12-bit bus-exchange architecture controlled by three select inputs (S0, S1, S2), enabling eight distinct path configurations including full disconnect, single-port exchange, and dual parallel exchange. Its FET-based switch cells deliver near-zero propagation delay and low capacitive loading (8 pF OFF-state).

Undershoot-protection circuitry actively monitors A/B port voltages and forces switch disablement when input falls below −2 V, preventing false conduction during signal transients. The device supports partial-power-down via Ioff, limiting backflow current to 10 µA when VCC = 0 V while maintaining isolation between powered and unpowered domains.

Key Specifications

Pinout & Package

TSSOP-56 (DGG) package: 12.0 mm × 4.4 mm footprint, 1.2 mm max height, 0.5 mm pitch, lead-free NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT16212CDGGR, SN74CBTD16212DGGR adds bus-hold at the cost of 3× higher ICC, while PI74CBT16212AE trades −2 V undershoot protection for marginal cost reduction-making SN74CBT16212CDGGR optimal for PCI-compliant and hot-plug applications demanding robust transient immunity and ultra-low static power.

Availability

SN74CBT16212CDGGR is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving architectures, and bus isolation systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74CBT16212CDGGR 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 electronic components.

The SN74CBT16212CDGGR belongs to TI's Widebus™ family of high-speed bus switches, engineered specifically for low-distortion, low-latency signal routing in computing, communications, and industrial control backplanes.

FAQ

What is the maximum undershoot voltage the SN74CBT16212CDGGR can withstand on its A and B ports?

The SN74CBT16212CDGGR provides active undershoot protection up to −2 V on both A and B ports. When voltage drops below this threshold, internal circuitry forces the switch into a guaranteed OFF state to prevent unintended conduction or latch-up. This specification is verified per test conditions in the official datasheet (SCDS146A, Section 6), with VOUTU measured at VOH−0.3 V under −2 V transient events.

Does the SN74CBT16212CDGGR support partial-power-down operation, and how is it implemented?

Yes, the SN74CBT16212CDGGR supports partial-power-down via its Ioff feature. When VCC = 0 V, Ioff limits current flow through the switch to ≤10 µA even with up to 5.5 V applied to I/O pins. This prevents damaging back-current from powered downstream circuits into the unpowered SN74CBT16212CDGGR, ensuring safe hot-swap capability in modular systems.

What is the ON-state resistance (ron) of the SN74CBT16212CDGGR, and how does it affect signal integrity?

The SN74CBT16212CDGGR has a typical ON-state resistance of 3 Ω, with a maximum of 6 Ω across the operating range. This low ron minimizes voltage drop and power loss across switched paths, preserving signal amplitude and reducing timing skew-critical for maintaining eye diagram margins in high-speed 24-bit parallel buses such as PCI-X or proprietary memory interfaces.

Can the SN74CBT16212CDGGR interface directly with 1.8-V or 2.5-V logic families without level shifters?

Yes, the SN74CBT16212CDGGR supports 0–5.5 V signaling on all data I/O pins, making it fully compatible with 0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, and 5-V logic families. Control inputs accept TTL or 5-V/3.3-V CMOS levels, and no external level translation is required-enabling seamless integration into mixed-voltage SoC and FPGA interconnects.

What package type and thermal characteristics apply to the SN74CBT16212CDGGR?

The SN74CBT16212CDGGR uses a 56-pin TSSOP (DGG) package measuring 12.0 mm × 4.4 mm with 0.5 mm pitch and 1.2 mm max height. Its thermal impedance is θJA = 64°C/W, and it is rated for operation from −40°C to +85°C. The package features NiPdAu lead finish and complies with JEDEC MO-153 standards.