Texas Instruments SN74CBT16245CDGGR

Overview

SN74CBT16245CDGGR from Texas Instruments is a 16-bit bidirectional FET bus switch IC with near-zero propagation delay (0.15 ns at 5 V), 3 Ω typical ON-state resistance, and undershoot protection up to −2 V on both A and B ports. It operates from 4 V to 5.5 V and supports mixed-voltage signaling (0.8 V to 5 V) for PCI interface and bus isolation applications.

For engineers reviewing the SN74CBT16245CDGGR datasheet, SN74CBT16245CDGGR pinout, SN74CBT16245CDGGR application, or SN74CBT16245CDGGR equivalent, key selection criteria include Ioff-enabled partial-power-down capability, 5.5 pF typical OFF-state I/O capacitance, TTL/CMOS-compatible control inputs, and TSSOP-48 package compatibility with high-density PCB layouts.

Technical Context

The SN74CBT16245CDGGR implements two independent 8-bit FET bus switches, each controlled by dedicated OE inputs (1OE, 2OE), enabling flexible 8-bit or 16-bit data path configuration. Its active undershoot-protection circuitry monitors A/B port voltage and forces OFF-state retention during −2 V transients.

Each switch channel features low-impedance bidirectional conduction (ron = 3 Ω typ), minimal signal distortion (Cio(OFF) = 5.5 pF), and Ioff support that blocks backflow current during power-down. Control inputs accept TTL or 5-V/3.3-V CMOS logic levels, while data I/Os tolerate 0–5.5 V signals regardless of VCC state.

Key Specifications

Pinout & Package

TSSOP-48 package (DGG), 12.6 mm × 6.2 mm × 1.2 mm body height, JEDEC MO-153 compliant, lead-free NIPDAU finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT16245CDGGR, SN74CBTD16245DGGR adds integrated current limiting at the expense of higher ON-resistance, while SN74LVC16245ADGGR trades undershoot protection and speed for lower voltage operation and reduced cost in non-transient-prone environments.

Availability

SN74CBT16245CDGGR is available at Aetrix Electronics and suitable for PCI interface design, memory interleaving architectures, and low-distortion signal gating applications requiring stable component supply and long-term industrial availability.

Supply support for SN74CBT16245CDGGR 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 decades of expertise in high-speed logic and interface solutions.

The SN74CBT16245CDGGR belongs to TI's Widebus™ family of FET bus switches, engineered specifically for high-bandwidth, low-latency bus isolation and signal routing in computing, communications, and industrial control systems.

FAQ

What is the maximum undershoot voltage the SN74CBT16245CDGGR can withstand on its A and B ports?

The SN74CBT16245CDGGR features active undershoot-protection circuitry rated for −2 V on both A and B ports. This protection ensures the switch remains reliably in the OFF state during negative transients, preventing unintended conduction or latch-up. The specification is verified per test conditions in the official datasheet (SCDS139, Section 5), with VCC = 5.5 V and switch disabled.

Does the SN74CBT16245CDGGR support partial-power-down operation, and how is it implemented?

Yes, the SN74CBT16245CDGGR supports partial-power-down via its Ioff feature. When VCC = 0 V, the device limits backflow current to ≤10 µA even with up to 5.5 V applied to I/O pins. This behavior is inherent to its FET architecture and requires no external circuitry. The Ioff specification is guaranteed over −40°C to 85°C and is validated per JESD 78 Class II latch-up testing.

What is the typical ON-state resistance of the SN74CBT16245CDGGR, and how does it affect signal integrity?

The SN74CBT16245CDGGR has a typical ON-state resistance (ron) of 3 Ω at VCC = 4.5 V and IO = 30 mA. This low ron minimizes voltage drop and power dissipation during signal pass-through, preserving logic thresholds and reducing jitter in high-speed data paths. Measured values range from 3 Ω to 6 Ω across process/voltage/temperature, ensuring consistent performance in 5-V bus applications.

Can the SN74CBT16245CDGGR interface between different logic families, such as 1.8-V and 5-V systems?

Yes, the SN74CBT16245CDGGR supports 0–5.5 V signaling on its data I/Os independent of VCC, enabling direct interfacing between 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. No external level shifters are required, though VCC must be set to ≥4 V to ensure proper internal biasing and undershoot protection functionality.

What package type and thermal characteristics apply to the SN74CBT16245CDGGR?

The SN74CBT16245CDGGR uses a 48-pin TSSOP package (DGG) with 12.6 mm × 6.2 mm footprint and 1.2 mm max height. Its thermal impedance is θJA = 70°C/W under standard JEDEC conditions. The package is RoHS-compliant, lead-free (NIPDAU), and rated MSL Level-1 (unlimited floor life at ≤30°C/60% RH), making it suitable for automated SMT assembly and industrial thermal environments.