Texas Instruments SN74AUC2G125DCUR

Overview

SN74AUC2G125DCUR from Texas Instruments is a dual 3-state bus buffer gate optimized for 1.65-V to 1.95-V operation, delivering ±8-mA output drive at 1.8 V, sub-1-V operability down to 0.8 V, max propagation delay of 1.8 ns at 1.8 V, and Ioff support for partial-power-down mode. It serves as a level-shifting, bidirectional bus isolation component in low-voltage memory interfaces and portable SoC interconnects.

For engineers reviewing the SN74AUC2G125DCUR datasheet, SN74AUC2G125DCUR pinout, SN74AUC2G125DCUR application, or SN74AUC2G125DCUR equivalent, key selection criteria include its 1.8-V optimized timing, 3-state output control per channel, Ioff-enabled power sequencing compatibility, and VSSOP-8 (DCU) package footprint for space-constrained PCB layouts.

Technical Context

This device implements two independent noninverting buffers, each with dedicated 3-state output-enable (OE) control. Each channel operates across 0.8 V–2.7 V supply range but is characterized and specified for 1.65 V–1.95 V VCC, enabling robust mixed-mode signal interfacing between 1.8-V logic domains and 3.3-V or 2.5-V peripherals.

The Ioff circuitry actively disables outputs during power-down, blocking reverse current flow when VCC = 0 V while inputs/outputs remain biased up to 3.6 V. Input thresholds scale with VCC (VIH = 0.65×VCC, VIL = 0.35×VCC), ensuring noise margin stability across voltage corners.

Key Specifications

Pinout & Package

VSSOP-8 (DCU) package: 2.3-mm × 2.0-mm body, 0.5-mm lead pitch, 0.9-mm max height, exposed pad not present, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC2G125DCUR and 74AUP2G125GM,115, the SN74AUC2G125DCUR uniquely balances sub-2-ns speed, 10-μA quiescent current, and 3.6-V I/O tolerance in a standard VSSOP-8 footprint-making it optimal for high-density, battery-sensitive 1.8-V systems requiring both performance and power efficiency.

Availability

SN74AUC2G125DCUR is available at Aetrix Electronics and suitable for mobile memory interfaces, FPGA I/O expansion, wearable sensor hubs, and industrial PLC I/O modules requiring stable component supply across long production lifecycles.

Supply support for SN74AUC2G125DCUR 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 connectivity technologies, with over 90 years of innovation in high-reliability, high-performance IC design.

The SN74AUC2G125 belongs to TI's AUC Sub-1-V Little Logic family, engineered specifically for ultra-low-voltage, high-speed digital interfacing in portable, battery-powered, and energy-constrained applications.

FAQ

What is the recommended power-up sequence for SN74AUC2G125DCUR to ensure reliable 3-state behavior?

TI specifies that OE pins must be held high (disabled) until VCC reaches stable operating voltage. To guarantee high-impedance state during power ramp, tie each OE to VCC through a pullup resistor ≥10 kΩ. This prevents bus contention during startup. The SN74AUC2G125DCUR does not incorporate internal power-on reset, so external OE control is essential for deterministic initialization.

Can SN74AUC2G125DCUR safely interface between a 1.8-V FPGA and a 3.3-V ADC without external level shifters?

Yes. The SN74AUC2G125DCUR supports 3.6-V I/O tolerance on all inputs and outputs regardless of VCC. When powered at 1.8 V, it accepts 0–3.3-V input signals and drives 0–3.3-V loads, making it suitable for unidirectional bridging from FPGA to ADC. However, bidirectional use requires separate transmit/receive paths due to its non-bidirectional architecture.

Does SN74AUC2G125DCUR support hot-swap or live-insertion in powered-backplane applications?

Yes - the Ioff feature actively disables outputs when VCC = 0 V, blocking current flow even if inputs or outputs are biased to 3.6 V. This protects both the SN74AUC2G125DCUR and upstream/downstream circuitry during insertion into a live backplane. TI validates this capability per JESD78 Class II latch-up testing (>100 mA).

What is the maximum capacitive load SN74AUC2G125DCUR can drive while maintaining 1.8-ns propagation delay?

The 1.8-ns max tpd is specified at CL = 15 pF and VCC = 1.8 V. Driving loads >15 pF increases propagation delay nonlinearly - e.g., at 30 pF, tpd rises to 2.6 ns. For designs requiring strict <2-ns timing, keep net capacitance ≤12 pF using short traces, minimal vias, and avoid stubs. TI provides load circuit details in Figure 1 of SCES532D.

Is the VSSOP-8 (DCU) package of SN74AUC2G125DCUR compatible with standard SSOP-8 (DCT) footprints?

No. The SN74AUC2G125DCUR uses VSSOP-8 (DCU) with 2.3 mm × 2.0 mm body and 0.5-mm pitch, whereas SSOP-8 (DCT) measures 3.0 mm × 3.0 mm with 0.65-mm pitch. These are mechanically incompatible - DCU requires dedicated land pattern per TI drawing DCU0008A. Attempting to mount SN74AUC2G125DCUR in a DCT footprint will cause solder bridging and open circuits.