onsemi NLSF3T125MNR2

Overview

NLSF3T125MNR2 from onsemi is a high-speed CMOS quad bus buffer with 3-state control inputs, fabricated in silicon gate CMOS technology. It delivers 3.8 ns typical propagation delay at 5.0 V, supports 2.0–5.5 V supply operation, features TTL-compatible inputs (VIL = 0.8 V, VIH = 2.0 V), full 5.0 V CMOS output swing, and operates across −40 °C to +85 °C - used for level translation and bus isolation in mixed-voltage digital systems.

For engineers reviewing the NLSF3T125MNR2 datasheet, pinout, applications, or equivalent options, key selection criteria include 3-state enable timing (tPZL/tPLZ ≤ 8.5 ns @ 5 V), input overvoltage tolerance up to 7.0 V, 3.3 V ↔ 5.0 V interface capability, and QFN-16 package compatibility with space-constrained PCB layouts.

Technical Context

The NLSF3T125MNR2 implements four independent non-inverting buffers, each with an active-high 3-state output enable (OE) controlling high-impedance state entry. Its three-stage internal architecture ensures balanced propagation delays and high noise immunity, with inputs tolerant to 7.0 V regardless of VCC.

Designed for voltage-level bridging, it accepts TTL-level inputs while delivering rail-to-rail CMOS outputs - enabling reliable interfacing between 3.3 V logic domains and legacy 5.0 V buses. Input structures provide power-down protection and latch-up immunity exceeding 300 mA per I/O.

Key Specifications

Pinout & Package

Package: QFN-16 (3 mm × 3 mm, 0.5 mm pitch, exposed thermal pad), case 485G. RoHS-compliant, Pb-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad bus buffer applications.

Compared with SN74LVC125APWR and 74LCX125MTCX, the NLSF3T125MNR2 uniquely supports true 5.0 V output swing with 5 V-tolerant inputs across 2.0–5.5 V supply - making it the only option among the three capable of robust 3.3 V ↔ 5.0 V bidirectional level translation without external components.

Availability

NLSF3T125MNR2 is available at Aetrix Electronics and suitable for industrial bus isolation, microcontroller I/O expansion, hot-swappable module interfaces, and legacy system upgrades requiring stable component supply and long-term manufacturability.

Supply support for NLSF3T125MNR2 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, logic, and sensor solutions for automotive, industrial, and cloud infrastructure markets.

The NLSF3T125MNR2 belongs to onsemi's high-speed logic family designed specifically for voltage-level bridging and bus isolation in mixed-supply digital systems - emphasizing robustness, timing precision, and interoperability across legacy and modern logic families.

FAQ

What is the maximum input voltage the NLSF3T125MNR2 can safely tolerate?

The NLSF3T125MNR2 supports DC input voltages from −0.5 V to +7.0 V, independent of VCC level. This overvoltage tolerance allows safe interfacing of 5.0 V signals into 3.3 V or 2.5 V systems without external clamping diodes or level shifters - a key advantage confirmed in the Absolute Maximum Ratings table of the official datasheet.

Does the NLSF3T125MNR2 support true 5.0 V CMOS output swing?

Yes, the NLSF3T125MNR2 delivers full rail-to-rail CMOS output swing up to 5.0 V when operated at VCC = 5.0 V, with VOH ≥ 4.4 V and VOL ≤ 0.1 V under 50 mA load. This capability is explicitly specified in the DC Electrical Characteristics table and enables direct driving of legacy 5 V TTL/CMOS loads - a distinguishing feature versus 3.3 V-only logic buffers.

What is the function of the NC pins on the NLSF3T125MNR2 QFN-16 package?

Pins 14 and 15 of the NLSF3T125MNR2 are designated as No-Connect (NC) terminals - they are not internally bonded and must remain unconnected on the PCB. The datasheet's marking diagram and pinout figure confirm these pins serve no electrical function and should not be tied to VCC, GND, or any other net to avoid unintended coupling or mechanical stress on the die.

How does the NLSF3T125MNR2 handle power sequencing when VCC is 0 V?

The NLSF3T125MNR2 output structures remain protected even when VCC = 0 V, preventing damage from back-drive or floating-bus conditions. This behavior is documented in the datasheet's "Power Down Protection" feature and verified by the absolute maximum rating for VOUT (output in 3-state: −0.5 V to VCC + 0.5 V), enabling safe hot-insertion and battery-backup operation.

Is the exposed thermal pad on the NLSF3T125MNR2 QFN-16 package electrically connected?

Yes, the exposed pad (EP) on the NLSF3T125MNR2 is internally connected to GND. Per the datasheet's mechanical outline and recommended layout guidelines, it must be soldered to a PCB thermal pad tied to the system ground plane to ensure proper thermal dissipation, EMI suppression, and mechanical reliability - failure to do so may degrade timing performance and long-term reliability.