Texas Instruments 74CBTD3384CDGVRE4

Overview

74CBTD3384CDGVRE4 from Texas Instruments is a 10-bit TTL-compatible FET bus switch IC with dual 5-bit configurable channels, 3 Ω typical ON-state resistance, −2 V undershoot protection on A/B ports, and integrated VCC-level-shifting diode enabling 5-V-to-3.3-V bidirectional translation. It supports memory interleaving and bus isolation in industrial control backplanes.

For engineers reviewing the 74CBTD3384CDGVRE4 datasheet, 74CBTD3384CDGVRE4 pinout, 74CBTD3384CDGVRE4 application, or 74CBTD3384CDGVRE4 equivalent, key selection criteria include Ioff partial-power-down capability, 0.15 ns propagation delay, 5 pF OFF-state I/O capacitance, and TVSOP-24 package compatibility with high-density PCB layouts.

Technical Context

The device implements two independent 5-bit FET-based analog switches controlled by separate OE inputs (1OE, 2OE), enabling either dual 5-bit or single 10-bit operation. Each switch channel features active undershoot-protection circuitry that detects −2 V transients and forces OFF-state isolation without latch-up.

Level shifting is achieved via an integrated series diode between VCC and the internal switch node, allowing 5-V logic inputs to drive 3.3-V outputs while maintaining bidirectional signal flow. The Ioff specification ensures <10 µA leakage when VCC = 0 V, supporting safe partial-power-down in mixed-voltage systems.

Key Specifications

Pinout & Package

74CBTD3384CDGVRE4 is housed in a 24-pin TVSOP (DGV) package measuring 4.9 mm × 3.9 mm × 1.2 mm, optimized for high-density surface-mount assembly with 0.4 mm lead pitch and exposed thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384CPWR and SN74CBTD3384CDBR, the 74CBTD3384CDGVRE4 delivers optimal balance of industrial temperature range, minimal PCB footprint, and proven reliability in high-density backplane interfaces-making it the preferred choice for space-constrained industrial embedded systems.

Availability

74CBTD3384CDGVRE4 is available at Aetrix Electronics and suitable for memory interleaving, bus isolation, and industrial backplane interface applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for 74CBTD3384CDGVRE4 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 industrial, automotive, and communications markets.

The 74CBTD3384CDGVRE4 belongs to TI's CBTD family of high-speed FET bus switches, engineered specifically for low-latency, low-distortion signal routing in mixed-voltage digital systems with stringent power sequencing and ESD robustness requirements.

FAQ

What is the maximum undershoot voltage the 74CBTD3384CDGVRE4 can withstand on its A/B ports?

The 74CBTD3384CDGVRE4 provides active undershoot protection up to −2 V on both A and B ports, as verified in the absolute maximum ratings and undershoot characterization section of the datasheet. This protection operates independently of VCC state and ensures the switch remains in the OFF state during transient negative excursions, preventing false conduction or latch-up. The 74CBTD3384CDGVRE4 achieves this via dedicated sensing circuitry integrated into each FET channel.

Does the 74CBTD3384CDGVRE4 support true bidirectional level shifting between 5-V and 3.3-V logic domains?

Yes, the 74CBTD3384CDGVRE4 supports true bidirectional level shifting using an integrated diode in series with VCC, enabling 5-V inputs to produce 3.3-V outputs without external components. When a 5-V signal drives the A port, the diode drop reduces the effective voltage seen at the B port to approximately 3.3 V. Conversely, a 3.3-V signal on B passes directly to A with negligible loss due to the FET's low ron. This behavior is confirmed in Figure 5 and the level shifter test circuit description for the 74CBTD3384CDGVRE4.

What is the thermal performance of the 74CBTD3384CDGVRE4 in its TVSOP package?

The 74CBTD3384CDGVRE4 in the TVSOP (DGV) package has a junction-to-ambient thermal resistance (θJA) of 86°C/W, as specified in the absolute maximum ratings table. This value assumes standard JEDEC high-K board conditions (2S2P) and reflects the thermal limitation imposed by the small 4.9 mm × 3.9 mm footprint and 0.4 mm lead pitch. For continuous operation at full rated current, derating per the SOA curve is required; the 74CBTD3384CDGVRE4 is intended for intermittent or low-duty-cycle switching in thermally managed layouts.

How does the Ioff feature of the 74CBTD3384CDGVRE4 protect downstream circuitry during partial power-down?

The Ioff feature of the 74CBTD3384CDGVRE4 limits leakage current to ≤10 µA when VCC = 0 V and any I/O port is biased between 0 V and 5.5 V, preventing damaging backflow current into unpowered sections of a system. This is achieved through internal transistor biasing that disables all FET channels and isolates the A/B ports from VCC/GND rails. The 74CBTD3384CDGVRE4 meets JESD 78 Class II latch-up immunity, ensuring robustness during mixed-rail power sequencing in complex embedded platforms.

Can the 74CBTD3384CDGVRE4 be used as a single 10-bit switch or only as two independent 5-bit switches?

The 74CBTD3384CDGVRE4 can be configured either as two independent 5-bit switches (using 1OE and 2OE separately) or as a single 10-bit switch (by tying 1OE and 2OE together). Its internal architecture consists of ten identical FET switches grouped into two banks of five, with no electrical coupling between banks. The function table and logic diagram confirm that OE control is per-bank, and the 74CBTD3384CDGVRE4 datasheet explicitly states it "can be used as two 5-bit bus switches or as one 10-bit bus switch" without performance trade-offs.