Texas Instruments SN74AHCT245MPWREP

Overview

SN74AHCT245MPWREP from Texas Instruments is an enhanced-product octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data bus communication in harsh environments. It operates from 4.5 V to 5.5 V, features TTL-compatible inputs (VIH = 2 V, VIL = 0.8 V), supports –55°C to +125°C operation, and delivers ±8 mA output drive at 5 V - used in aerospace avionics backplane interfaces requiring radiation-tolerant signal isolation.

For engineers reviewing the SN74AHCT245MPWREP datasheet, SN74AHCT245MPWREP pinout, SN74AHCT245MPWREP application, or SN74AHCT245MPWREP equivalent, key selection criteria include its 20-pin TSSOP package, direction-controlled bidirectional flow, OE-gated 3-state outputs, and extended-temperature reliability for defense-grade system integration.

Technical Context

The SN74AHCT245MPWREP implements dual-bus transceivers with independent DIR control per channel group and a global OE input enabling simultaneous 3-state disable of all A↔B paths. Its logic-level translation capability allows interfacing 3.3-V controllers with 5-V buses via VIH = 2 V compatibility.

Functional modes are strictly defined by OE/DIR combinations: OE = L enables bidirectional transfer (DIR = L → B→A; DIR = H → A→B); OE = H forces all outputs into high-impedance regardless of DIR state - critical for bus arbitration and hot-swap isolation in mission-critical systems.

Key Specifications

Pinout & Package

SN74AHCT245MPWREP uses a 20-pin TSSOP (PW) package with 6.5 mm × 6.4 mm outline and 0.65 mm lead pitch. Body size is 6.5 mm × 4.4 mm; maximum height is 1.2 mm. Pin 1 index area is marked on top surface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74AHCT245MPWREP, SN74AHCT245PWRE lacks extended temperature and traceability controls but offers identical functionality at lower cost, while SN54AHCT245FK provides superior environmental ruggedness in ceramic packaging at the expense of size and procurement lead time.

Availability

SN74AHCT245MPWREP is available at Aetrix Electronics and suitable for avionics data routing, satellite onboard computing, defense radar backplanes, and medical imaging timing distribution requiring stable component supply across extended product lifecycles.

Supply support for SN74AHCT245MPWREP 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 high-reliability components for industrial, automotive, and aerospace markets.

The SN74AHCT245MPWREP belongs to TI's Enhanced Product line - engineered specifically for defense, aerospace, and medical applications demanding controlled baselines, full traceability, and extended lifecycle support.

FAQ

What is the operating temperature range for SN74AHCT245MPWREP?

The SN74AHCT245MPWREP is rated for operation from –55°C to +125°C. This extended temperature range is validated per its Enhanced Product qualification and supports deployment in aerospace, defense, and downhole industrial environments where thermal extremes are routine. The specification is guaranteed across the full range, not just typical conditions.

Does SN74AHCT245MPWREP support level translation between 3.3-V and 5-V logic?

Yes, SN74AHCT245MPWREP supports bidirectional level translation. Its TTL-compatible inputs accept VIH ≥ 2 V and VIL ≤ 0.8 V, allowing direct connection to 3.3-V CMOS outputs while driving 5-V bus loads. No external resistors or translators are needed - the device inherently bridges these voltage domains within its specified operating conditions.

How does the OE pin behave during power-up in SN74AHCT245MPWREP?

During power-up, SN74AHCT245MPWREP enters a high-impedance state if OE is left floating or undriven. To ensure safe bus isolation, TI recommends tying OE to VCC via a pullup resistor (e.g., 10 kΩ). This guarantees all outputs remain in 3-state until firmware explicitly asserts OE = LOW - preventing unintended bus contention in safety-critical systems.

What is the maximum capacitive load SN74AHCT245MPWREP can drive while maintaining timing specs?

SN74AHCT245MPWREP is characterized for CL ≤ 50 pF in its switching specifications. At this load, tPLH/tPHL remains ≤ 8.7 ns (VCC = 5 V, TA = 25°C). Driving >50 pF increases propagation delay and may degrade signal integrity; TI advises limiting trace+load capacitance to 50 pF for guaranteed timing compliance in high-speed designs.

Is SN74AHCT245MPWREP pin-compatible with standard SN74AHCT245 variants?

Yes, SN74AHCT245MPWREP shares identical pinout, package (20-pin TSSOP), and electrical behavior with commercial SN74AHCT245PWRE and military SN54AHCT245FK variants. All three use the same DIR/OE control logic and A/B I/O mapping - enabling drop-in replacement where environmental qualifications permit.