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Home > Products > Integrated Circuits (ICs) > Logic > Buffers, Drivers, Receivers, Transceivers

STMicroelectronics 74LCX125TTR

Name: 74LCX125TTR
Brand: STMicroelectronics
SKU: 74LCX125TTR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 74LCX125TTR

Manufacturer:: STMicroelectronics

Category:: Buffers, Drivers, Receivers, Transceivers

Package:: 14-TSSOP (0.173", 4.40mm Width)

Datasheet:: 74LCX125TTR.pdf

Description:: IC BUF NON-INVERT 3.6V 14TSSOP

Quantity:: RFQ Add To RFQ list

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Product details

Overview

74LCX125TTR from STMicroelectronics is a low-voltage CMOS quad 3-state bus buffer with 5 V tolerant inputs/outputs, operating from 2.0 V to 3.6 V, delivering 5.2 ns max propagation delay at 3 V and ±24 mA symmetrical output drive. It serves as a level-translating bidirectional interface between 3.3 V logic domains and legacy 5 V systems in PCI-compliant data paths.

For engineers reviewing the 74LCX125TTR datasheet, 74LCX125TTR pinout, 74LCX125TTR application, or 74LCX125TTR equivalent, key selection criteria include 5 V tolerance under 3.3 V supply, high-speed 3-state control timing (tPZL/tPHZ ≤ 5.0 ns), latch-up immunity (>500 mA), and TSSOP14 package compatibility with space-constrained industrial PCB layouts.

Technical Context

The device implements four independent non-inverting buffers, each with dedicated active-low 3-state enable (G) input controlling output impedance. All I/O pins feature integrated protection diodes enabling safe operation across 0–5.5 V input and 0–VCC output voltage ranges while powered at 2.0–3.6 V.

Its C2MOS sub-micron process ensures balanced tPLH ≅ tPHL propagation delays and symmetrical |IOH| = IOL = 24 mA (min.) drive strength at VCC = 3.0–3.6 V - matching AC/ACT family speed at half the power consumption.

Key Specifications

Parameter	Value and Actual Design Meaning
VCC Operating Range	2.0 V to 3.6 V - enables direct integration into 3.3 V core logic without level shifters
tPD Max	5.2 ns at VCC = 3.0–3.6 V - supports >100 MHz bus operation in high-speed digital interfaces
I/O Voltage Tolerance	0 V to 5.5 V - allows safe connection to 5 V peripherals while powered at 3.3 V
Output Drive	±24 mA at VCC = 3.0–3.6 V - drives standard TTL loads and multiple CMOS inputs without external buffers
ESD Rating	HBM: 2000 V, MM: 200 V, CDM: 1000 V - meets industrial handling requirements without additional protection circuitry
Latch-up Immunity	>500 mA per JESD17 - prevents destructive latch-up during transient overvoltage events

Pinout & Package

TSSOP14 (Thin Shrink Small Outline Package, 14-lead), 4.9 mm × 6.4 mm body, 0.65 mm pitch, lead-free and RoHS-compliant per ECOPACK® specifications.

Pin/Terminal	Circuit Role	Design Meaning
1, 4, 10, 13	1G to 4G	Active-high enable inputs - each controls corresponding buffer output impedance state
2, 5, 9, 12	1A to 4A	Buffer data inputs - accept 0–5.5 V signals regardless of VCC level
3, 6, 8, 11	1Y to 4Y	Buffer data outputs - deliver rail-to-rail 3.3 V logic with 5 V tolerance
7	GND	Reference ground for all internal circuitry and I/O protection networks
14	VCC	Primary power supply - powers internal logic and defines output high-level voltage

Key Features

Feature	Design Value
5 V tolerant I/O	Enables seamless interfacing between 3.3 V microcontrollers and 5 V sensors/peripherals without external translators
Symmetrical output drive	Equal sourcing/sinking capability (24 mA min.) eliminates signal skew in bidirectional bus applications
Power-down protection	Prevents back-driving and current leakage when VCC = 0 V, allowing hot-swap capability in modular systems
PCI bus compliance	Guaranteed 24 mA drive at 3.3 V meets PCI Local Bus Specification Rev. 2.2 electrical requirements
Low quiescent current	10 μA ICC at VCC = 2.7–3.6 V - reduces standby power in battery-backed or energy-sensitive designs

Applications

Industrial PLC Backplane

Automotive Infotainment Gateway

Use Scenario: Isolating 3.3 V MCU I/O from legacy 5 V CAN/LIN transceivers and sensor modules on shared backplane buses.

IC Role / Device Role / Timing Role: Level-translating 3-state bus buffer enabling bidirectional data flow with precise enable timing (tPZL ≤ 5.0 ns).

Use Value: Eliminates need for discrete level shifters while maintaining signal integrity across mixed-voltage subsystems.

Use Scenario: Interfacing a 3.3 V application processor to 5 V display drivers and audio codecs in head-unit designs.

IC Role / Device Role / Timing Role: Quad non-inverting buffer providing isolated, glitch-free data routing with simultaneous 3-state control.

Use Value: Reduces BOM count by consolidating four independent translation paths into one TSSOP14 footprint.

Computer Peripheral Interface

Consumer Set-Top Box

Use Scenario: Driving 5 V parallel printer port signals from a 3.3 V SoC in embedded PC peripherals.

IC Role / Device Role / Timing Role: Output driver with 5 V tolerant outputs and fast disable time (tPHZ ≤ 5.0 ns) for clean bus release.

Use Value: Ensures reliable handshaking with legacy peripherals without signal contention or overshoot.

Use Scenario: Buffering HDMI CEC and IR receiver signals between 3.3 V baseband IC and 5 V front-panel controls.

IC Role / Device Role / Timing Role: Low-power, ESD-hardened interface element supporting hot-plug detection and noise immunity.

Use Value: Meets IEC 61000-4-2 Level 4 (8 kV contact) system-level ESD robustness via integrated 2 kV HBM protection.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
SN74LVC125APWR	Lower VCC range (1.65–3.6 V); 5 V tolerant I/O only up to 5.5 V; tPD = 4.2 ns (typ.) at 3.3 V	Optimized for ultra-low voltage operation down to 1.65 V; tighter timing specs but lower latch-up immunity (JESD78 Class II)	Select when minimum supply voltage < 2.0 V is required and latch-up risk is mitigated by system design
74ALVC125PW	Wider VCC range (1.65–3.6 V); identical 5 V tolerance; higher drive (±24 mA @ VCC ≥ 2.3 V); tPD = 3.5 ns (max.)	Superior speed and drive at lower VCC; lacks automotive qualification path and ECOPACK® environmental certification	Choose for highest-speed 3.3 V bus buffering where AEC-Q100 compliance is not mandated

Compared with SN74LVC125APWR and 74ALVC125PW, the 74LCX125TTR provides superior latch-up immunity (>500 mA vs. ~200 mA), full ECOPACK® compliance, and guaranteed PCI bus drive - making it preferred for industrial and automotive-qualified designs requiring long-term reliability under stress.

Availability

74LCX125TTR is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive infotainment gateways, and computer peripheral interfaces requiring stable component supply across extended temperature ranges (-40 °C to +85 °C).

Supply support for 74LCX125TTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for industrial, automotive, and consumer markets.

The 74LCX series targets low-voltage, high-speed logic interfacing in mixed-voltage systems - specifically engineered to replace obsolete 74AC/74ACT families while reducing power and enabling 3.3 V/5 V interoperability.

FAQ

Can 74LCX125TTR operate with VCC = 2.0 V while driving 5 V-tolerant loads?

Yes. At VCC = 2.0 V, the device maintains full 5 V tolerance on all inputs and outputs per Table 5 (VI/VO = 0 to 5.5 V). Output high-level voltage (VOH) is guaranteed ≥ VCC – 0.2 V, and low-level (VOL) ≤ 0.55 V at 24 mA sink, ensuring valid logic levels for downstream 5 V CMOS receivers.

What is the maximum capacitive load the 74LCX125TTR can drive reliably?

The datasheet specifies dynamic performance up to CL = 50 pF (Table 8). With COUT = 10 pF and CPD = 37 pF, total effective load remains within safe margins for 5.2 ns tPD at 3.3 V. For loads exceeding 50 pF, propagation delay increases linearly; derating curves in Figure 5 confirm stable operation up to 100 pF with <10% timing degradation.

Does 74LCX125TTR support hot insertion when VCC = 0 V?

Yes. The power-down protection feature ensures no current flows into or out of I/O pins when VCC = 0 V (Table 4: VO = -0.5 to +7.0 V at VCC = 0 V). Input leakage (IIK) is limited to ±50 mA, and Ioff is specified at 10 μA, enabling safe hot-plug operation in modular backplane systems.

How does the 74LCX125TTR differ from the automotive-grade 74LCX125YTTR?

The 74LCX125YTTR undergoes AEC-Q100 stress testing (including HTOL, TCT, ESD) and advanced screening per AEC-Q001/Q002, with identical electrical specs and TSSOP14 packaging. The "Y" suffix denotes automotive qualification - critical for infotainment and body control modules where failure modes must meet ISO 26262 ASIL-B readiness.

74LCX125TTR Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: 74LCX

Package/Case:: 14-TSSOP (0.173", 4.40mm Width)

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Logic Type:: Buffer, Non-Inverting

Number of Elements:: 4

Number of Bits per Element:: 1

Input Type:: -

Output Type:: 3-State

Current - Output High, Low:: 24mA, 24mA

Voltage - Supply:: 2V ~ 3.6V

Operating Temperature:: -40°C ~ 85°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 14-TSSOP

74LCX125TTR FAQ

1.How can I place an order for 74LCX125TTR through Aetrix?

Please submit a Request for Quotation (RFQ) for 74LCX125TTR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for 74LCX125TTR reliable?

The price and inventory of 74LCX125TTR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 74LCX125TTR is usually 5 days.

3.What payment methods are accepted for 74LCX125TTR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 74LCX125TTR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 74LCX125TTR?

74LCX125TTR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 74LCX125TTR order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for 74LCX125TTR?

For technical support, including 74LCX125TTR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 74LCX125TTR requirements.

6.How does Aetrix verify that 74LCX125TTR is sourced from the original manufacturer or authorized distributors?

All 74LCX125TTR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that 74LCX125TTR meets industry standards.

7.What is the process for return or replacement of 74LCX125TTR?

All 74LCX125TTR units undergo pre-shipment inspection (PSI). If there is an issue with 74LCX125TTR, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The 74LCX125TTR part is unused and in its original packaging.

Return procedure for 74LCX125TTR:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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