Diodes Incorporated 74LVC1G125Z-7

Overview

74LVC1G125Z-7 from Diodes Incorporated is a single non-inverting 3-state buffer IC designed for voltage-level shifting and signal isolation in mixed-voltage digital systems. It operates from 1.65V to 5.5V, tolerates 5.5V inputs, delivers ±24mA output drive at 3.3V, and features IOFF circuitry for partial power-down protection-used in notebook I/O expansion, USB peripheral interface logic, and embedded controller bus buffering.

For engineers reviewing the 74LVC1G125Z-7 datasheet, 74LVC1G125Z-7 pinout, 74LVC1G125Z-7 application, or 74LVC1G125Z-7 equivalent, key selection criteria include its 1.65–5.5V supply range, 5.5V-tolerant inputs, IOFF-enabled power-down isolation, and SOT553 footprint compatibility with space-constrained portable electronics designs.

Technical Context

This device implements a CMOS-based non-inverting buffer with active-low 3-state output enable (OE), enabling bidirectional bus control and signal gating without inversion. Its IOFF circuit actively disables outputs during power-down, preventing backflow current when VCC = 0V while inputs/outputs remain biased up to 5.5V.

The SOT553 package (1.6mm × 1.6mm × 0.62mm, 0.5mm pitch) supports high-density PCB layouts, and the input threshold scales with VCC (e.g., VIH = 0.7×VCC at 4.5–5.5V), ensuring reliable TTL- and LVTTL-compatible interfacing across supply voltages.

Key Specifications

Pinout & Package

SOT553 (1.6mm × 1.6mm × 0.62mm, 0.5mm lead pitch) - ultra-compact surface-mount package with exposed pad not electrically connected; optimized for thermal performance and board area reduction in portable devices.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DBVR, the 74LVC1G125Z-7 saves 42% board area and improves thermal dissipation in thin-profile devices; versus 74AUP1G125GW, it delivers 6× higher output current for robust signal integrity in noisy industrial environments.

Availability

74LVC1G125Z-7 is available at Aetrix Electronics and suitable for notebook I/O expansion, USB peripheral interface logic, and embedded controller bus buffering requiring stable component supply and long-term production continuity.

Supply support for 74LVC1G125Z-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, energy-efficient components for computing, industrial, and consumer markets.

The 74LVC logic family targets low-voltage, mixed-supply digital interfacing with emphasis on voltage tolerance, power-down safety, and compact packaging for portable and space-constrained applications.

FAQ

Can 74LVC1G125Z-7 operate with VCC = 1.5V?

No. The recommended minimum operating voltage is 1.65V per the datasheet's Recommended Operating Conditions table. At 1.5V, parameters like VOH, VOL, and tpd are not guaranteed, and functionality may fail during temperature extremes or process variation. Data retention is supported down to 1.5V, but only in static, non-switching states.

Is the NC pin on SOT553 electrically connected?

No. Pin 6 of the SOT553 package is marked "NC" (No Connection) in the official Diodes Inc. datasheet and pin assignment diagrams. It is not bonded internally and must remain unconnected on the PCB - no trace, pad, or solder should contact this terminal.

What is the maximum capacitive load this buffer can drive reliably?

Based on measured Cpd = 19pF (outputs enabled) and typical tpd = 4.5ns at 3.3V, the device reliably drives ≤30pF loads while maintaining specified timing. Driving >50pF may increase propagation delay beyond 6.0ns and cause marginal setup/hold timing in high-speed interfaces like SPI or I²C.

Does IOFF protect against reverse current when only GND is disconnected?

No. IOFF requires VCC = 0V to activate its internal blocking circuitry. If only GND is disconnected while VCC remains applied, the device remains powered and IOFF does not engage. Full protection requires both VCC and GND to be de-energized, or use of external isolation diodes in critical backfeed paths.