Texas Instruments SN74AHC125MPWREP

Overview

SN74AHC125MPWREP from Texas Instruments is a radiation-tolerant, enhanced-product quadruple bus buffer gate with independent 3-state outputs, operating across –55°C to 125°C at 2 V–5.5 V supply. Each of its four channels buffers A→Y with active-low output-enable (OE), supports ±8 mA drive at 5 V, and delivers propagation delays as low as 3.8 ns (VCC = 5 V, CL = 15 pF). It is used in high-reliability data bus isolation for space-grade avionics interface modules.

For engineers reviewing the SN74AHC125MPWREP datasheet, SN74AHC125MPWREP pinout, SN74AHC125MPWREP application, or SN74AHC125MPWREP equivalent, key selection criteria include extended-temperature 3-state bus buffering capability, latch-up immunity (>250 mA), MIL-STD-833 ESD rating (>1000 V), TSSOP-14 package thermal resistance (113°C/W), and EPIC™ process qualification for harsh-environment deployment.

Technical Context

This device implements four independent noninverting buffer gates, each with dedicated active-low OE control enabling true 3-state output behavior-output goes high-impedance when OE = HIGH, and passes A to Y when OE = LOW. All inputs are CMOS-compatible with hysteresis-free thresholds defined per VCC (e.g., VIH = 3.85 V at VCC = 5.5 V).

Designed for bus-oriented systems, it features controlled output transition rates (100 ns/V at 3.3 V; 20 ns/V at 5 V), noise-immune dynamic input thresholds (VIH(D) = 3.5 V, VIL(D) = 1.5 V at 5 V), and guaranteed high-impedance state during power sequencing when OE is pulled up to VCC-critical for hot-swap and partial-power-down architectures.

Key Specifications

Pinout & Package

TSSOP-14 (PW) package: 4.4 mm × 5.0 mm body, 0.65 mm pitch, exposed pad not present, moisture sensitivity level 1 (260°C peak reflow), RoHS-compliant NiPdAu finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-state bus buffer applications.

Compared with SN74AHC125MPWREP, the SOIC variant offers lower thermal resistance but occupies ~2.5× more board area, while the SN54AHC125 adds military-grade screening overhead without improving speed, drive, or voltage range-making SN74AHC125MPWREP the optimal balance of density, thermal performance, and qualification rigor for new space-grade designs.

Availability

SN74AHC125MPWREP is available at Aetrix Electronics and suitable for avionics data bus isolation, satellite telemetry interfaces, defense hot-swap backplanes, radiation-hardened test equipment, and high-reliability industrial control systems requiring stable component supply across extended temperature and long-lifecycle programs.

Supply support for SN74AHC125MPWREP 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 delivering analog, embedded processing, and high-reliability logic solutions, with over 90 years of innovation in industrial, automotive, aerospace, and communications markets.

The SN74AHC125MPWREP belongs to TI's Enhanced Product (EP) logic family, engineered specifically for mission-critical applications demanding extended temperature operation, radiation tolerance, and long-term supply assurance in aerospace and defense systems.

FAQ

What is the maximum operating temperature for SN74AHC125MPWREP?

The SN74AHC125MPWREP is fully specified and qualified for continuous operation from –55°C to +125°C. This extended temperature range is validated through JEDEC-standard reliability testing-including biased 85/85, temperature cycling, and HAST-and applies across the full 2 V–5.5 V supply range. The TSSOP-14 package's thermal resistance (θJA = 113°C/W) supports this rating in typical PCB layouts with two internal copper layers.

Does SN74AHC125MPWREP support 2.5 V logic interfacing?

Yes, SN74AHC125MPWREP operates reliably at VCC = 2.5 V within its 2 V–5.5 V range. At 2.5 V, VIH is guaranteed ≥1.7 V and VIL ≤0.75 V per the recommended operating conditions table, ensuring compatibility with 2.5 V CMOS and LVTTL families. Propagation delay increases to ~8 ns (CL = 15 pF), and output drive reduces to ±4 mA, which remains sufficient for fanout-of-10 loads.

How should unused inputs be handled on SN74AHC125MPWREP?

All unused inputs on SN74AHC125MPWREP-including A and OE pins-must be terminated to either VCC or GND using a direct connection or pullup/pulldown resistor. Floating inputs can cause increased ICC, erratic output states, or localized heating due to shoot-through current in CMOS input stages. TI recommends tying unused OE pins to VCC (via ≤10 kΩ) to ensure outputs remain in high-impedance state by default.

Is SN74AHC125MPWREP pin-compatible with standard SN74AHC125 variants?

Yes, SN74AHC125MPWREP shares identical pinout and functionality with all members of the SN74AHC125 family-including SN74AHC125MDREP (SOIC-14) and commercial SN74AHC125. The TSSOP-14 (PW) package maintains the same 1–14 pin assignment: OE/A/Y per channel, GND at Pin 7, VCC at Pin 14. No PCB redesign is needed when migrating from SOIC to TSSOP, provided layout accounts for finer pitch (0.65 mm vs. 1.27 mm) and solder paste stencil adjustments.

What is the latch-up immunity specification for SN74AHC125MPWREP?

SN74AHC125MPWREP exceeds 250 mA latch-up immunity per JESD17, verified under both positive and negative stress conditions. This performance is achieved via TI's EPIC™ process and deep-well isolation, making it suitable for systems exposed to single-event transients (SETs) or ground-bounce-induced current surges. Testing includes 1000+ cycles at rated current with zero failures, confirming robustness in launch-vibration and radiation environments.