NXP Semiconductors 74LVC1G125GX125

Overview

74LVC1G125GX125 from Nexperia is a single 3-state bus buffer/line driver with Schmitt-trigger inputs, operating from 1.65 V to 5.5 V supply. It enables level translation between 3.3 V and 5 V logic domains, supports partial power-down via IOFF, and delivers ±24 mA output drive at 3.0 V - used in I²C bus isolation, sensor interface signal conditioning, and mixed-voltage microcontroller GPIO expansion.

For engineers reviewing the 74LVC1G125GX125 datasheet, 74LVC1G125GX125 pinout, 74LVC1G125GX125 application, or 74LVC1G125GX125 equivalent, key selection criteria include its X2SON5 (SOT1226-3) 5-terminal thermal-enhanced package, 0.8 × 0.8 × 0.32 mm footprint, IOFF-enabled power-down leakage < ±2 μA, and propagation delay as low as 0.5 ns at 5 V.

Technical Context

This device implements a non-inverting buffer with active-low 3-state enable (OE), where output Y follows input A when OE = LOW and enters high-impedance state when OE = HIGH. Schmitt-trigger inputs tolerate slow-rising signals up to 10 ns/V transition rate, enabling robust operation with noisy or RC-filtered sources.

The IOFF circuitry actively disables both output and input paths when VCC = 0 V, blocking backflow current and supporting hot-swap and partial-power-down system architectures. Input voltage tolerance to 5.5 V allows direct interfacing with 5 V TTL outputs even when powered at 1.65 V.

Key Specifications

Pinout & Package

X2SON5 (SOT1226-3) package: plastic thermal-enhanced extremely thin small outline, no leads, 5 terminals, body size 0.8 × 0.8 × 0.32 mm, side-wettable flanks not present, pin 1 index located at lower-left corner below marking code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74LVC1G125GV and 74LVC1G125GW, the 74LVC1G125GX125 offers the smallest footprint (0.64 mm²), lowest thermal resistance, and highest reliability in automated SMT lines due to its X2SON5 geometry - making it optimal for wearables, medical sensors, and compact industrial modules.

Availability

74LVC1G125GX125 is available at Aetrix Electronics and suitable for industrial sensor interface, I²C bus isolation, and microcontroller GPIO expansion requiring stable component supply across automotive, medical, and industrial OEM programs.

Supply support for 74LVC1G125GX125 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 focused on essential efficiency technologies, delivering high-performance logic, discrete, and MOSFET solutions for automotive, industrial, and consumer markets.

The 74LVC1G125GX125 belongs to Nexperia's LVC logic family, engineered for ultra-low power consumption, wide supply flexibility, and robust operation in mixed-voltage embedded systems - targeting space-constrained, thermally demanding applications.

FAQ

What is the maximum input voltage rating for 74LVC1G125GX125 when VCC = 1.65 V?

The 74LVC1G125GX125 supports overvoltage-tolerant inputs up to 5.5 V regardless of VCC level. When powered at 1.65 V, inputs may safely accept 0–5.5 V signals - enabling direct interfacing with 5 V microcontrollers or sensors without external level shifting. This capability is confirmed in Table 3 (Pin description) and Section 2 (Features and benefits) of the official Nexperia datasheet Rev. 17.1.

Does 74LVC1G125GX125 support hot-swap operation, and how is it implemented?

Yes, 74LVC1G125GX125 supports hot-swap operation via its IOFF circuitry. When VCC = 0 V, the IOFF feature disables both input and output paths, limiting power-off leakage current to < ±2 μA (Table 7). This prevents damaging backflow current through the device during live insertion/removal - a requirement verified in Section 1 (General description) and Table 5 (Limiting values) of the Nexperia datasheet.

What is the propagation delay of 74LVC1G125GX125 at VCC = 3.3 V and 25 °C?

At VCC = 3.3 V and Tamb = 25 °C, the typical propagation delay (tpd) of 74LVC1G125GX125 is 2.1 ns, with a maximum of 4.5 ns over -40 °C to +85 °C (Table 8). These values apply to the A-to-Y path and are measured with 50 pF load and ≤2.5 ns input rise/fall times - consistent with high-speed digital control signaling in real-time embedded systems.

Can 74LVC1G125GX125 be used as a level shifter between 1.8 V and 5 V logic domains?

Yes, 74LVC1G125GX125 functions as a unidirectional level shifter: when VCC = 1.8 V, its 5.5 V-tolerant inputs accept 5 V signals, and its output swings between 0 V and 1.8 V. The device does not translate in reverse (output-to-input), and bidirectional translation requires two units. This behavior is explicitly documented in Section 1 and validated in Table 6 (Recommended operating conditions).

What is the thermal resistance (RθJA) of the X2SON5 package used by 74LVC1G125GX125?

The X2SON5 (SOT1226-3) package of 74LVC1G125GX125 has a total power dissipation derating factor of 3.0 mW/K above 67 °C (Table 5). While absolute RθJA is not published, this derating implies an effective junction-to-ambient thermal resistance of approximately 333 K/W - significantly lower than TSSOP5 (303 K/W) and SC-74A (263 K/W) variants, confirming its thermal-enhanced design for compact, high-density layouts.