Texas Instruments SN74LVCZ245ANSR

Overview

SN74LVCZ245ANSR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between 3.3-V and 5-V buses. It operates from 2.7 V to 3.6 V, accepts 5.5-V-tolerant inputs, delivers 6.3 ns max propagation delay at 3.3 V, and supports hot insertion via Ioff and power-up 3-state logic-enabling use in mixed-voltage industrial backplanes and FPGA I/O bridging.

For engineers reviewing the SN74LVCZ245ANSR datasheet, SN74LVCZ245ANSR pinout, SN74LVCZ245ANSR application, or SN74LVCZ245ANSR equivalent, key selection criteria include voltage translation capability (3.3-V VCC with 5-V input tolerance), guaranteed 3-state isolation during power sequencing, latch-up immunity (>100 mA per JESD 78 Class II), and SOP-20 package compatibility with legacy board layouts.

Technical Context

The SN74LVCZ245ANSR implements dual-directional bus control using a single DIR input to select A→B or B→A data flow, while OE enables/disables all outputs simultaneously into high-impedance state. Its Ioff circuitry actively disables outputs when VCC = 0, preventing current backflow during hot insertion.

It supports mixed-mode signal operation: all I/O ports tolerate 0–5.5 V input voltage regardless of VCC (2.7–3.6 V), enabling direct interfacing between 5-V legacy peripherals and 3.3-V microcontrollers without external level shifters. Power-up 3-state ensures outputs remain high-Z until VCC exceeds 1.5 V or OE is actively controlled.

Key Specifications

Pinout & Package

SOP-20 (NS package), 7.4 mm × 5.3 mm body, 1.27 mm pitch, 2.65 mm max height, JEDEC MS-013 compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A, SN74LVCZ245ANSR delivers lower ground bounce and tighter VOHV undershoot specs for improved signal fidelity; compared with 74ALVC16245, it offers drop-in compatibility in existing 8-bit SOP-20 layouts but trades channel density for footprint continuity.

Availability

SN74LVCZ245ANSR is available at Aetrix Electronics and suitable for industrial PLC backplanes, FPGA-to-MCU bridging, and automotive diagnostic gateways requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74LVCZ245ANSR 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 SN74LVCZ245ANSR belongs to TI's LVCZ logic family, engineered specifically for robust mixed-voltage system interfacing-prioritizing hot-insertion safety, wide input voltage tolerance, and low-noise switching in mission-critical industrial control applications.

FAQ

What is the maximum input voltage the SN74LVCZ245ANSR can tolerate on its I/O pins?

The SN74LVCZ245ANSR accepts input voltages from 0 V to 5.5 V on all A and B port pins, independent of VCC level (2.7–3.6 V). This allows direct interfacing with 5-V TTL or CMOS devices without external clamping or level-shifting circuitry. The absolute maximum rating remains –0.5 V to 6.5 V, but sustained operation above 5.5 V risks reliability degradation.

Does the SN74LVCZ245ANSR support hot insertion, and how is it implemented?

Yes, the SN74LVCZ245ANSR supports hot insertion via two integrated features: Ioff circuitry disables outputs when VCC = 0, limiting off-state current to ±5 µA, and power-up 3-state forces all outputs into high-impedance mode until VCC exceeds 1.5 V. These mechanisms prevent bus contention and back-current flow when inserted into a live 5-V backplane, meeting industrial hot-swap requirements.

What is the propagation delay specification for SN74LVCZ245ANSR at 3.3 V, and under what test conditions?

The SN74LVCZ245ANSR has a maximum propagation delay (tpd) of 6.3 ns at VCC = 3.3 V ± 0.3 V, measured under standard load conditions (CL = 30 pF, input transition rate ≤6 ns/V). This value applies to both A→B and B→A data paths and is guaranteed across the full operating temperature range (–40°C to 85°C), supporting high-speed synchronous bus protocols.

Can SN74LVCZ245ANSR be used in systems with slow power-up ramps, and what design guidance applies?

Yes, the SN74LVCZ245ANSR is qualified for slow-ramp systems: its power-up 3-state remains active until VCC exceeds 1.5 V, and the recommended ∆t/∆VCC ramp rate is ≤150 µs/V. To ensure robust isolation above 1.5 V, TI recommends tying OE to VCC through a pullup resistor-minimum value determined by the driver's current-sinking capability, typically 10 kΩ for standard logic drivers.

How does the latch-up performance of SN74LVCZ245ANSR compare to industry standards?

The SN74LVCZ245ANSR exceeds 100 mA latch-up immunity per JESD 78 Class II, significantly surpassing the minimum 100 mA requirement for Class II devices. This performance is validated under worst-case stress conditions and ensures reliable operation in electrically noisy industrial environments where transient coupling could otherwise trigger parasitic SCR conduction.