Texas Instruments SN74LVC1G240DSFR

Overview

SN74LVC1G240 from Texas Instruments is a single-channel inverting buffer/driver with 3-state output, designed for signal conditioning and bus isolation in low-voltage digital systems. It operates from 1.65V to 5.5V, delivers ±24mA drive at 3.3V, achieves 3.7ns max propagation delay, and supports 5.5V-tolerant inputs - enabling level translation in mixed-supply interfaces such as microcontroller GPIO expansion or sensor interface staging.

For engineers reviewing the SN74LVC1G240 datasheet, SN74LVC1G240 pinout, SN74LVC1G240 application, or SN74LVC1G240 equivalent, key selection criteria include its Ioff-enabled live insertion capability, balanced CMOS 3-state output architecture, sub-4ns timing at 3.3V, ultra-low 10μA ICC, and NanoFree™ package compatibility with space-constrained PCB layouts.

Technical Context

The SN74LVC1G240 implements a true inverting logic function (Y = NOT A) with active-low 3-state control via OE. Its CMOS input structure accepts voltages up to 5.5V independent of VCC, enabling down-translation from higher-voltage logic domains into 1.8V/2.5V/3.3V systems without external level shifters.

When OE is high, the output enters high-impedance state with leakage ≤10μA (Ioff), supporting partial power-down and back-drive protection. The device uses balanced push-pull output stages capable of sourcing and sinking equal current (±24mA at 3.3V), ensuring symmetrical rise/fall times and robust driving into light capacitive loads (≤50pF).

Key Specifications

Pinout & Package

SN74LVC1G240 is available in multiple ultra-small packages including DSF (SON, 6-pin, 1mm × 1mm), DRY (SON, 6-pin), YZP (DSBGA, 5-pin), DCK (SC70, 5-pin), and DBV (SOT-23, 5-pin). The DSF variant - referenced by the suffix "DSFR" - uses a 6-pin SON package with exposed thermal pad, optimized for thermal performance and board area reduction in portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G240, SN74LVC1G04DSFR removes bus-sharing capability but simplifies control logic, while SN74AUP1G240DSFR trades 40% higher propagation delay for 20× lower quiescent current - making each alternative optimal only under specific power-speed-layout constraints.

Availability

SN74LVC1G240 is available at Aetrix Electronics and suitable for LED indicator driving, digital signal re-driving, transmission line termination, controller reset hold, and mixed-voltage interface bridging requiring stable component supply across automotive infotainment, industrial PLC I/O modules, and portable medical sensors.

Supply support for SN74LVC1G240 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 for industrial, automotive, and consumer applications.

The SN74LVC1G240 belongs to TI's LVC (Low-Voltage CMOS) logic family, engineered for high-speed, low-power, mixed-voltage interoperability in space-constrained digital systems - particularly targeting signal integrity preservation in portable and modular electronics.

FAQ

What is the maximum operating temperature for SN74LVC1G240?

The SN74LVC1G240 is rated for continuous operation from –40°C to +125°C ambient temperature. This extended range is validated per JEDEC JESD78 Class II latch-up testing and supports deployment in under-hood automotive modules, industrial motor drives, and outdoor IoT gateways where thermal cycling exceeds commercial-grade limits. The DSF package's thermal resistance (RθJA = 132°C/W) further enhances reliability in thermally dense layouts.

Does SN74LVC1G240 require external pull-up resistors on the OE pin?

Yes - to ensure the output remains in high-impedance during power-up or power-down, OE must be tied to VCC through an external pull-up resistor. TI specifies the minimum value based on the driver's current-sinking capability; a 10kΩ resistor is recommended for most applications, balancing fast enable/disable transitions against static current draw. Leaving OE floating risks bus contention or unintended output activation.

Can SN74LVC1G240 drive a 50pF capacitive load while meeting timing specs?

Yes - the SN74LVC1G240 is characterized to drive loads up to 50pF while maintaining all switching specifications, including 3.7ns max tpd at 3.3V. For loads exceeding 50pF, TI recommends adding a series damping resistor near the output to suppress ringing and maintain signal integrity. Layout best practices (short traces, ground plane, 0.1μF decoupling) are essential to achieve guaranteed performance.

Is SN74LVC1G240 compatible with 5V logic inputs when powered at 3.3V?

Yes - the SN74LVC1G240 features over-voltage tolerant inputs rated to 5.5V, allowing direct connection to 5V logic signals even when VCC = 3.3V. This eliminates external level-shifting components in mixed-supply systems such as interfacing a 5V sensor output to a 3.3V microcontroller GPIO. Input clamp current is limited to ±50mA, so external current limiting remains necessary only under fault conditions.

What is the purpose of the NC pin in the DSF (6-pin SON) package of SN74LVC1G240?

The NC (No Connect) pin in the DSF package of SN74LVC1G240 is not internally bonded and serves no electrical function. It must remain unconnected on the PCB to prevent parasitic coupling, solder bridging, or EMI susceptibility. Unlike thermal pads or unused pins tied to GND/VCC, this pin has no mechanical or thermal role - its presence accommodates package mold design and does not affect SN74LVC1G240 functionality or reliability.