Nexperia USA Inc. 74AHCT245PW,118

Overview

74AHCT245PW,118 from Nexperia is an octal 3-state bus transceiver with TTL-compatible input thresholds and bidirectional data flow controlled by DIR and active-low OE pins. It operates from 4.5 V to 5.5 V, supports -40 °C to +125 °C industrial temperature range, features overvoltage-tolerant inputs up to 5.5 V, and delivers propagation delay as low as 3.5 ns (VCC = 5 V, CL = 15 pF), enabling high-speed level translation in mixed-voltage microcontroller I/O expansion interfaces.

For engineers reviewing the 74AHCT245PW,118 datasheet, 74AHCT245PW,118 pinout, 74AHCT245PW,118 application, or 74AHCT245PW,118 equivalent, key selection criteria include its TTL-level input compatibility, 3-state output drive capability, thermal-enhanced TSSOP20 package, and verified performance in 5 V ↔ 3.3 V bus bridging under industrial temperature stress.

Technical Context

The 74AHCT245PW,118 implements a dual-rail bidirectional bus interface using complementary CMOS logic with Schmitt-trigger inputs for noise immunity. Its DIR pin selects data direction (A→B or B→A), while OE enables/disables all outputs simultaneously into high-impedance state - critical for shared-bus arbitration in embedded systems.

Unlike the AHC variant, the AHCT version guarantees TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5–5.5 V), ensuring reliable interfacing with legacy 5 V TTL logic while maintaining CMOS power efficiency and latch-up immunity exceeding 100 mA per JESD78 Class II Level A.

Key Specifications

Pinout & Package

TSSOP20 plastic thin shrink small outline package (SOT360-1); 20-pin surface-mount with 0.65 mm pitch, 4.4 mm body width, and thermal pad optimized for industrial ambient operation up to +125 °C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74AHCT245D,118, the 74AHCT245PW,118 saves 42 % board area and improves thermal response in compact enclosures; versus SN74AHCT245PWR, it offers Nexperia's extended industrial temperature validation and tighter propagation delay consistency across voltage corners.

Availability

74AHCT245PW,118 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, embedded test equipment backplanes, and medical diagnostic data acquisition requiring stable component supply across extended temperature ranges.

Supply support for 74AHCT245PW,118 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

Nexperia is a global semiconductor expert delivering high-performance logic, analog, and MOSFET solutions with focus on reliability, efficiency, and miniaturization for industrial, automotive, and computing markets.

The 74AHCT245PW,118 belongs to Nexperia's advanced logic family designed specifically for robust voltage-level translation and bus isolation in harsh-environment embedded systems where signal integrity and long-term supply stability are critical.

FAQ

Can 74AHCT245PW,118 operate reliably at 3.3 V supply?

No - the 74AHCT245PW,118 is TTL-input compatible and specified only for 4.5 V to 5.5 V operation. At 3.3 V, VIH minimum (2.0 V) is met, but VOH and VOL degrade beyond specification limits, and propagation delay increases significantly. Use 74AHC245PW,118 instead for 3.3 V systems.

What is the maximum capacitive load this device can drive while maintaining timing specs?

The datasheet guarantees timing performance up to 50 pF load capacitance at VCC = 4.5–5.5 V. Driving >50 pF causes measurable tpd increase (e.g., +2.5 ns at 100 pF) and may violate setup/hold margins in high-speed interfaces. For heavier loads, add series termination or buffer stages.

Is the thermal pad on the TSSOP20 package electrically connected?

No - the exposed thermal pad (pin 1 index area) is not internally connected to GND or any signal. Per Nexperia's note, it may remain floating or be soldered to a GND plane for thermal improvement, but must never be electrically tied to VCC or signal nets to avoid parasitic coupling.

How does OE pin behavior differ from DIR in terms of timing control?

OE controls output enable/disable state globally: HIGH forces all A/B pins into high-impedance regardless of DIR state. DIR only affects data direction when OE is LOW. The disable time (tdis = 6.0–12.5 ns) is longer than propagation delay (tpd = 3.5–11.0 ns), so OE must be asserted before DIR changes to prevent bus contention.