Texas Instruments SN74CBT16209DLR

Overview

SN74CBT16209DLR from Texas Instruments is an 18-bit TTL-compatible bus-exchange switch operating from –40°C to 85°C, featuring 5-Ω on-state resistance, 0.25 ns typical propagation delay (A↔B), and dual 9-bit configurable data routing via S0–S2 select lines. It enables bidirectional signal path switching in high-speed memory and peripheral interconnects.

For engineers reviewing the SN74CBT16209DLR datasheet, SN74CBT16209DLR pinout, SN74CBT16209DLR application, or SN74CBT16209DLR equivalent, key selection criteria include on-resistance matching, TTL-level compatibility, bus-exchange mode timing, and DL-package thermal performance at 1.2 W max dissipation.

Technical Context

The SN74CBT16209DLR implements a CMOS-based analog bus switch architecture with independent channel control, supporting both 18-bit pass-through and 9-bit A/B port exchange modes. Its logic-controlled flow uses three select inputs (S0–S2) to configure nine distinct connection states between two 9-bit port pairs (A1/A2 and B1/B2).

Each of the 18 switch channels exhibits matched on-resistance (4–8 Ω at VCC = 4.5 V), low off-capacitance (7.5 pF), and sub-nanosecond propagation delay under 50-pF load. Input and output pins are fully TTL-compatible with VIH = 2 V and VIL = 0.8 V thresholds.

Key Specifications

Pinout & Package

SN74CBT16209DLR is packaged in a 48-pin Plastic Shrink Small-Outline (DL) package, 300-mil body width, with 0.025-inch lead pitch and exposed pad not present. Pin count and layout match JEDEC MO-153 specification.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT16209DLR, SN74CBTD16210DLR adds voltage translation but increases on-resistance and power consumption, while 74LVC16245ADL,118 provides direction control at lower voltage but lacks bus-exchange functionality and 5-V tolerance - making SN74CBT16209DLR optimal for pure 5-V, low-skew, configurable switching.

Availability

SN74CBT16209DLR is available at Aetrix Electronics and suitable for memory interleaving, peripheral multiplexing, test access port switching, and legacy bus bridging requiring stable component supply and long-term industrial availability.

Supply support for SN74CBT16209DLR 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 founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The CBT (Crosspoint Bus Transceiver) family, including SN74CBT16209DLR, was designed for high-speed, low-latency digital signal routing in 5-V systems where minimal propagation delay and TTL compatibility are critical.

FAQ

What is the maximum continuous current rating per channel for SN74CBT16209DLR?

The SN74CBT16209DLR supports up to 128 mA continuous current per switch channel, verified under absolute maximum ratings. This allows direct drive of standard 5-V TTL loads without external current limiting. Exceeding this value risks thermal degradation or latch-up. The 4–8 Ω on-resistance ensures voltage drop remains below 1 V at rated current, preserving signal integrity in SN74CBT16209DLR implementations.

Does SN74CBT16209DLR support level shifting between different logic voltages?

No, SN74CBT16209DLR does not support level shifting. It operates strictly within a 4–5.5 V VCC range and features TTL-compatible input thresholds (VIH = 2 V, VIL = 0.8 V) optimized for 5-V systems. For mixed-voltage applications, TI recommends SN74CBTD16210DLR instead. SN74CBT16209DLR must be used with matched 5-V signaling on both A and B ports to ensure reliable operation.

How many distinct switching configurations does SN74CBT16209DLR support via its select inputs?

SN74CBT16209DLR supports eight distinct switching configurations using its three select inputs (S0, S1, S2), as defined in the function table. These include two disconnect states and six active routing modes - four single-path (A1→B1, A1→B2, A2→B1, A2→B2) and two dual-path (A1↔B1 + A2↔B2, A1↔B2 + A2↔B1). All configurations are implemented in hardware without internal latches, making SN74CBT16209DLR a purely combinational bus-exchange device.

What is the thermal performance difference between SN74CBT16209DLR and the WD-package variant?

SN74CBT16209DLR (DL package) has a maximum power dissipation of 1.2 W at TA = 55°C, while the WD-package SN54CBT16209 supports only 0.85 W under identical conditions. The DL package's plastic construction and larger thermal pad area improve heat conduction over the ceramic WD variant. This makes SN74CBT16209DLR better suited for sustained high-current operation in commercial-temperature applications, whereas SN74CBT16209DLR's thermal profile is validated for continuous 128 mA per channel at 85°C ambient.

Can SN74CBT16209DLR be used in hot-swap applications?

SN74CBT16209DLR is not specifically characterized for hot-swap operation. While its absolute maximum ratings include –0.5 V to 7 V on all I/O pins and clamp current limits (±50 mA), it lacks integrated hot-swap protection features such as slew-rate control or undervoltage lockout. Use in live-insertion scenarios requires external current-limiting resistors and sequencing circuitry. For robust hot-swap designs, consider dedicated hot-swap controllers alongside SN74CBT16209DLR rather than relying on the device alone.