onsemi 74VCX245WMX

Overview

74VCX245WMX from ON Semiconductor is a low-voltage bidirectional transceiver with 3.6V-tolerant I/O, designed for bus interface applications between mixed-voltage domains. It operates from 1.4V to 3.6V V_CC, delivers ±24 mA drive at 3.0V, achieves 3.5 ns max propagation delay, and features 3-STATE outputs controlled by OE (active-low) and T/R direction select - used in voltage-level translation between 1.8V/2.5V/3.3V subsystems.

For engineers reviewing the 74VCX245WMX datasheet, pinout, applications, or equivalent options, key selection criteria include bidirectional 3.6V I/O tolerance, power-off high-impedance behavior, live insertion support, and SOIC-20 package compatibility with JEDEC MS-013 footprint.

Technical Context

The 74VCX245WMX implements eight non-inverting bidirectional buffers with independent 3-STATE control per port via active-low OE and direction-select T/R inputs. Its CMOS design enables rail-to-rail output swing (0V to V_CC) and 3.6V-tolerant I/O regardless of V_CC level (1.4V–3.6V), supporting hot-swap operation without external clamping.

It exhibits static drive capability of ±24 mA at 3.0V V_CC, propagation delay ≤3.5 ns (V_CC = 3.0–3.6V, C_L = 30 pF), and output skew ≤0.5 ns - enabling reliable timing in high-speed parallel bus interfaces such as memory expansion, FPGA I/O bridging, and microcontroller peripheral interconnects.

Key Specifications

Pinout & Package

74VCX245WMX is packaged in a 20-lead SOIC (JEDEC MS-013, 0.300" wide, package code M20B), with gull-wing leads and standard 1.27 mm pitch. The body dimensions are 7.50 mm × 10.30 mm × 2.65 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245APWR and 74ALVC245MTCX, the 74VCX245WMX uniquely supports 1.4V operation and guarantees 3.6V I/O tolerance down to minimum V_CC, making it optimal for designs requiring widest voltage flexibility in SOIC-20 form factor.

Availability

74VCX245WMX is available at Aetrix Electronics and suitable for memory expansion interfaces, FPGA I/O bridging, hot-swappable module interfaces, and legacy system voltage translation requiring stable component supply and long-term industrial availability.

Supply support for 74VCX245WMX 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, logic, and discrete devices for automotive, industrial, cloud computing, and IoT applications.

The 74VCX logic family was developed by Fairchild (now part of ON Semiconductor) to deliver high-speed, low-voltage bidirectional translation with robust I/O tolerance - targeting mixed-voltage system integration in space-constrained industrial and communications equipment.

FAQ

What is the minimum V_CC voltage supported by the 74VCX245WMX?

The 74VCX245WMX supports a minimum V_CC of 1.4V, enabling operation in ultra-low-voltage domains such as 1.4V–1.6V microcontroller subsystems. This specification is confirmed in the Recommended Operating Conditions table of the datasheet, where V_CC min is explicitly listed as 1.4V across all temperature ranges.

Does the 74VCX245WMX support hot-plug or live insertion?

Yes, the 74VCX245WMX supports live insertion and withdrawal as documented in its Features list and Note 1 of the datasheet. This capability relies on power-off high-impedance I/O behavior and proper OE pull-up implementation - ensuring no bus contention occurs when the device is inserted into or removed from a powered system.

What package type does the 74VCX245WMX use, and is it RoHS compliant?

The 74VCX245WMX uses a 20-lead SOIC package (JEDEC MS-013, 0.300" wide, package code M20B). It is Pb-Free and RoHS compliant per JEDEC J-STD-020B, as stated in the Ordering Code section and Tape and Reel Specification page of the datasheet.

How does the 74VCX245WMX handle direction control and output enable functions?

The 74VCX245WMX uses two dedicated control inputs: T/R (pin 19) sets data flow direction (High = A→B, Low = B→A), and OE (pin 1) enables/disables both ports (Low = active, High = 3-STATE). These are asynchronous, level-sensitive controls with no clock dependency - allowing real-time bus arbitration in synchronous or asynchronous systems.

What is the maximum propagation delay for the 74VCX245WMX at 3.3V V_CC?

The maximum propagation delay (t_PHL/t_PLH) for the 74VCX245WMX is 3.5 ns at V_CC = 3.3V ±0.3V, C_L = 30 pF, and T_A = −40°C to +85°C - specified in the AC Electrical Characteristics table. This value applies to both A→B and B→A data paths under worst-case conditions.