Texas Instruments 74AUC1G125DCKRG4

Overview

74AUC1G125DCKRG4 from Texas Instruments is a single 3-state bus buffer gate optimized for 1.8-V operation, delivering ±8-mA output drive, 2.5-ns max propagation delay at 1.8 V/30 pF, 0.8–2.7-V supply range, and over-voltage tolerant I/Os up to 3.6 V. It serves as a high-speed signal redriver in compact portable logic interfaces.

For engineers reviewing the 74AUC1G125DCKRG4 datasheet, 74AUC1G125DCKRG4 pinout, 74AUC1G125DCKRG4 application, or 74AUC1G125DCKRG4 equivalent, key selection criteria include 3-state control timing, Ioff-enabled partial power-down capability, NanoFree™ SC70 package footprint, and ULTTL output compatibility with 50–65-Ω transmission lines under 15 cm.

Technical Context

The 74AUC1G125DCKRG4 implements a positive-logic noninverting buffer with active-low 3-state enable (OE), where output Y follows input A when OE is low and enters high-impedance when OE is high. Its ULTTL output structure dynamically adjusts impedance during transitions to suppress ringing while driving controlled-impedance lines directly.

It supports partial power-down via Ioff circuitry that disables outputs and limits back-drive current when VCC = 0 V, and features standard CMOS inputs requiring termination to VCC or GND - no floating inputs permitted. Absolute maximum I/O voltage tolerance is 3.6 V independent of VCC.

Key Specifications

Pinout & Package

74AUC1G125DCKRG4 uses the SC70-5 (DCK) package: 2.00 mm × 1.25 mm body, 0.65-mm pitch, 5-terminal surface-mount configuration with exposed pad not present. Pin 1 is OE (active-low enable), Pin 2 is A (input), Pin 3 is GND, Pin 4 is Y (3-state output), Pin 5 is VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125DCKR and 74AUP1G125GW,125, the 74AUC1G125DCKRG4 uniquely balances 2.5-ns speed at 1.8 V with ±8-mA drive and Ioff - making it the only option among the three qualified for high-fidelity, low-voltage, short-line redrive in portable electronics.

Availability

74AUC1G125DCKRG4 is available at Aetrix Electronics and suitable for mobile display interfaces, low-power sensor hubs, USB-C sideband routing, industrial digital I/O expansion, and compact FPGA I/O conditioning requiring stable component supply and consistent SC70-5 packaging.

Supply support for 74AUC1G125DCKRG4 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 logic solutions, with decades of innovation in high-speed, low-voltage logic families.

The 74AUC1G125DCKRG4 belongs to TI's AUC (Advanced Ultra-Low-Voltage CMOS) logic family - engineered specifically for sub-2-V, high-speed signal integrity in portable and battery-powered systems where power, size, and timing precision are critical.

FAQ

What is the maximum operating frequency supported by the 74AUC1G125DCKRG4?

The 74AUC1G125DCKRG4 supports data rates exceeding 250 MHz under optimal conditions: 1.8-V supply, 15-pF load, and proper PCB layout. This is derived from its 2.5-ns maximum propagation delay at 1.8 V/30 pF and confirmed in TI's AUC family documentation. Real-world frequency depends on trace length, termination, and loading - for 15-cm 50-Ω lines, reliable operation is validated up to 500 Mbps.

Does the 74AUC1G125DCKRG4 require external pull-up or pull-down resistors on unused pins?

Yes - all unused inputs of the 74AUC1G125DCKRG4, including A and OE, must be terminated to either VCC or GND per TI's recommendations. Floating CMOS inputs cause excessive current draw and potential oscillation. A 10-kΩ resistor is recommended; OE should be pulled up to VCC to ensure high-impedance state at power-up. GND and VCC pins require no external resistors but demand solid plane connections.

Can the 74AUC1G125DCKRG4 safely interface with 3.3-V logic signals?

Yes - the 74AUC1G125DCKRG4 has over-voltage tolerant I/Os rated to 3.6 V independent of VCC, allowing direct connection to 3.3-V drivers or receivers even when powered at 1.8 V. However, output swing remains limited to VCC (1.8 V), so receiving devices must recognize 1.8-V logic levels as valid HIGH. For bidirectional 3.3-V compatibility, level-shifting remains necessary.

What thermal considerations apply to the 74AUC1G125DCKRG4 in continuous operation?

The 74AUC1G125DCKRG4 exhibits low thermal risk: typical power dissipation is <0.5 mW at 10 MHz (Cpd = 15 pF), and its SC70 package has RθJA = 262.5°C/W. Even at worst-case 10-µA ICC and full ±8-mA output switching, junction temperature rise stays below 3°C above ambient - no heatsinking or airflow is required. Layout best practice is still to use GND flood fill beneath the package for noise reduction and minor thermal relief.

Is the 74AUC1G125DCKRG4 pin-compatible with other SC70-5 logic buffers like the SN74LVC1G125DCKR?

Yes - the 74AUC1G125DCKRG4 shares identical SC70-5 (DCK) mechanical footprint and pinout (OE-A-GND-Y-VCC) with SN74LVC1G125DCKR and 74AUP1G125GW,125. However, electrical behavior differs: AUC offers faster speed and lower VCC range, while LVC supports higher VCC and drive. PCB layout is interchangeable, but timing and voltage margins must be re-verified for each variant.