STMicroelectronics 74LVQ245MTR

Overview

74LVQ245MTR from STMicroelectronics is a low-voltage CMOS octal bus transceiver with 3-state outputs, designed for bidirectional asynchronous data transfer between two 8-bit buses. It operates from 2.0 V to 3.6 V, delivers 5.7 ns typical propagation delay at 3.3 V, supports 12 mA symmetrical drive (|IOH| = IOL), and features 75 Ω transmission line driving capability for noise-sensitive 3.3 V systems such as PCI bus interfaces.

For engineers reviewing the 74LVQ245MTR datasheet, 74LVQ245MTR pinout, 74LVQ245MTR application, or 74LVQ245MTR equivalent, key selection criteria include directional control logic (DIR), output enable (G), high-impedance isolation behavior, symmetrical drive strength, and 75 Ω line-driving compliance - all critical for signal integrity in mixed-voltage bus interfacing.

Technical Context

The device implements dual-bus bidirectional communication via a single DIR input that determines data flow direction (A→B or B→A), while G independently enables or disables all outputs into high-impedance state. Its C2MOS sub-micron process ensures latch-up immunity and 2 kV ESD protection on all I/O pins.

Propagation delays are balanced (tPLH ≅ tPHL), skew is tightly controlled (≤1.0 ns), and dynamic switching is guaranteed on 75 Ω transmission lines. Input thresholds meet TTL compatibility (VIH = 2.0 V min, VIL = 0.8 V max) across the full operating temperature range (–55°C to +125°C).

Key Specifications

Pinout & Package

74LVQ245MTR is housed in a 20-pin SOIC (Small Outline Integrated Circuit) package with standard 0.300-inch body width and 1.27 mm pitch. Pin 1 is marked by a beveled corner or dot; pin numbering follows counter-clockwise convention from top-left when viewed from the component side.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245APWR and 74ALVC245MTCX, the 74LVQ245MTR uniquely balances low noise (0.5 V VOLP), 75 Ω line driving guarantee, and PCI-compliant 24 mA drive - making it optimal for noise-sensitive, standards-constrained backplane and expansion bus designs.

Availability

74LVQ245MTR is available at Aetrix Electronics and suitable for PCI bus interface, low-voltage backplane interconnect, and embedded microcontroller expansion requiring stable component supply and long-term industrial lifecycle support.

Supply support for 74LVQ245MTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with vertical manufacturing capabilities and broad IP portfolio.

The 74LVQ series targets low-voltage, low-noise 3.3 V logic interoperability - specifically engineered for noise-sensitive bus bridging, backplane signaling, and mixed-voltage system integration where ESD robustness and transmission line integrity are design-critical.

FAQ

What is the maximum recommended operating temperature for 74LVQ245MTR?

The absolute maximum operating junction temperature is +125°C, and the recommended operating ambient temperature range is –55°C to +125°C per Table 5. This wide range supports deployment in industrial motor drives, outdoor telecom equipment, and automotive under-hood ECUs where thermal stress is significant.

Can 74LVQ245MTR operate reliably at 2.0 V supply?

Yes - the device is fully specified down to VCC = 2.0 V, with guaranteed VIH ≥ 2.0 V and VIL ≤ 0.8 V, and functional truth table operation from 1.2 V to 3.6 V. At 2.0 V, tPD increases to 11.0 ns (max), and drive strength reduces to ±8 mA, but remains sufficient for short-trace, low-speed local bus extension.

Is the 74LVQ245MTR pinout compatible with standard 74-series 245 devices?

Yes - it is pin- and function-compatible with 74LS245 and 74HC245, sharing identical 20-pin SOIC layout and DIR/G/A/B pin assignments. However, its 3.3 V optimized I/O thresholds and lower VCC range require careful verification of upstream/downstream logic families to avoid marginal interfacing.

Does 74LVQ245MTR require external pull-up or pull-down resistors on DIR or G inputs?

No - internal weak pull-downs are not present, and the inputs are CMOS with negligible leakage (±0.1 µA). External biasing is required only if floating states must be avoided during power-up or reset; a 10 kΩ pull-down on DIR ensures default A→B flow, while G should be actively driven or pulled low for default enable.