SN74LS240NG4 Equivalent & Substitute Parts

Part Overview

The SN74LS240NG4 is a logic buffer IC with inverting functionality, featuring 2 elements with 4 bits per element and 3-state output capability. This component is designed for digital signal buffering and inversion applications in TTL logic circuits. The part is discontinued at DiGi Electronics, making equivalent substitutes necessary for ongoing production and maintenance applications.

Substiute Parts

SN74LS240NG4

Texas InstrumentsIn Stock: 825SN74LS240NG4 Datasheet

Current PartRFQ

SN74LS240N

onsemiIn Stock: 2008SN74LS240N Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74LS240NG4 is determined by the following critical parameters:

• Logic Type: Buffer, Inverting (functional requirement)
• Number of Elements: 2 and Number of Bits per Element: 4 (pin configuration and functionality)
• Output Type: 3-State (electrical interface requirement)
• Current - Output High, Low: 15mA, 24mA (drive capability)
• Voltage - Supply: 4.75V ~ 5.25V (power supply compatibility)
• Operating Temperature: 0°C ~ 70°C (TA) (thermal operating range)
• Package / Case: 20-DIP (0.300", 7.62mm) (physical form factor and pin count)
• Mounting Type: Through Hole (assembly method)

The SN74LS240N from onsemi meets all these electrical and mechanical parameters, making it a direct functional equivalent.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS240N from onsemi is electrically and mechanically equivalent to the SN74LS240NG4. Both parts share identical logic functionality, pin configuration, electrical characteristics, and thermal operating range.

Selection between these parts should be based on compliance requirements. The SN74LS240NG4 carries ROHS3 compliance certification, while the SN74LS240N is RoHS non-compliant. For applications subject to RoHS regulations or environmental compliance mandates, the SN74LS240NG4 is the appropriate choice. For applications without such requirements, the SN74LS240N provides functional equivalence with current availability.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS240N directly replace the SN74LS240NG4 in my circuit?

A: Yes, from an electrical and mechanical standpoint. Both parts have identical logic type, element count, bit configuration, output type, current ratings, supply voltage range, operating temperature, and 20-DIP package. Pin-for-pin replacement is possible without circuit modification.

Q: What is the difference between these two parts?

A: The primary differences are manufacturer (Texas Instruments vs. onsemi), product status (discontinued vs. obsolete), and RoHS compliance (ROHS3 compliant vs. non-compliant). Electrical and functional specifications are identical.

Q: Does RoHS compliance matter for my application?

A: RoHS compliance is mandatory for products sold in the European Union and for many industrial and consumer applications. If your application or end market requires RoHS certification, use the SN74LS240NG4. If no such requirement exists, both parts are functionally equivalent.

Q: Are there any thermal or electrical performance differences?

A: No. Both parts operate across the same temperature range (0°C ~ 70°C) and deliver identical output current specifications (15mA high, 24mA low) at the same supply voltage range (4.75V ~ 5.25V).

Q: Will the through-hole 20-DIP package fit my PCB?

A: Yes, both parts use the identical 20-DIP (0.300", 7.62mm) through-hole package. PCB footprints and assembly methods are interchangeable.