SN75ALS171ADW Equivalent & Substitute Parts

Part Overview

The SN75ALS171ADW is a half-duplex RS422/RS485 transceiver IC manufactured by Texas Instruments, housed in a 20-SOIC surface mount package. This interface component features 3 drivers and 3 receivers with 60 mV receiver hysteresis, operating across a 4.75V to 5.25V supply voltage range and 0°C to 70°C temperature range. The part is currently classified as obsolete, making identification of equivalent and substitute components essential for ongoing system support and new design implementations.

Substiute Parts

SN75ALS171ADW

Texas InstrumentsIn Stock: 1965SN75ALS171ADW Datasheet

Current PartRFQ

SN65C1167ENSR

Texas InstrumentsIn Stock: 9568SN65C1167ENSR Datasheet

MFR RecommendedRFQ

SN75ALS170ADW

Texas InstrumentsIn Stock: 4397SN75ALS170ADW Datasheet

Parametric EquivalentRFQ

SN75ALS170DW

Texas InstrumentsIn Stock: 1199SN75ALS170DW Datasheet

Parametric EquivalentRFQ

SN75ALS171DW

Texas InstrumentsIn Stock: 2282SN75ALS171DW Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the SN75ALS171ADW is determined by strict alignment of the following critical parameters:

Primary Substitution Criteria:

• Protocol compatibility (RS422/RS485)
• Duplex mode (Half-duplex operation)
• Driver/Receiver configuration (3/3 topology)
• Package type (20-SOIC form factor)
• Receiver hysteresis (60 mV)
• Supply voltage range (4.75V ~ 5.25V minimum)
• Operating temperature range (0°C ~ 70°C minimum)

Substitute Categories:

Parametric Equivalents — Parts matching all critical electrical and mechanical parameters with identical or active product status:

• SN75ALS171DW
• SN75ALS170ADW
• SN75ALS170DW

Functional Substitute — Part with different duplex mode and driver/receiver count but compatible protocol and package considerations:

• SN65C1167ENSR (full-duplex, 2/2 configuration, different thermal and voltage specifications)

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Parametric Equivalents):

The SN75ALS171DW, SN75ALS170ADW, and SN75ALS170DW are parametric equivalents suitable for direct substitution in applications currently using the SN75ALS171ADW. All three parts maintain identical electrical specifications, package form factor, and compliance certifications (ROHS3). The primary distinction is product status: SN75ALS171DW, SN75ALS170ADW, and SN75ALS170DW are all active products with established supply chains, whereas the SN75ALS171ADW is obsolete. Selection among these three should be based on availability and inventory levels.

For Functional Substitution (SN65C1167ENSR):

The SN65C1167ENSR is a full-duplex transceiver with 2/2 driver/receiver configuration, differing fundamentally from the half-duplex 3/3 topology of the SN75ALS171ADW. This part is suitable only for applications where full-duplex operation and reduced channel count are acceptable. The SN65C1167ENSR offers extended operating temperature range (-40°C to 85°C) and wider supply voltage tolerance (4.5V to 5.5V), making it suitable for more demanding thermal environments. However, the 16-SOIC package differs from the 20-SOIC footprint, requiring PCB layout modifications.

Compliance and Regulatory Considerations:

All substitute parts maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment with the original component. No additional compliance verification is required for substitution within the same application context.

Frequently Asked Questions (FAQ)

Q: Can SN75ALS171DW be used as a direct replacement for SN75ALS171ADW?

A: Yes. The SN75ALS171DW is a parametric equivalent with identical electrical specifications, package type, and pin configuration. The primary difference is product status: SN75ALS171DW is active while SN75ALS171ADW is obsolete. No circuit modifications are required.

Q: What is the difference between the SN75ALS170 and SN75ALS171 series?

A: Both series are half-duplex RS422/RS485 transceivers with 3/3 driver/receiver configuration in 20-SOIC packages. The base product numbers (75ALS170 vs. 75ALS171) indicate different internal designs, but both maintain identical electrical parameters and are functionally interchangeable within the specified operating conditions.

Q: Why is the SN65C1167ENSR listed as a substitute if it has different specifications?

A: The SN65C1167ENSR is classified as a functional substitute rather than a parametric equivalent. It shares the same protocol (RS422/RS485), manufacturer, and compliance certifications, but operates in full-duplex mode with 2/2 driver/receiver configuration. It is suitable only for applications where these architectural differences are acceptable.

Q: Does the package size difference between 20-SOIC and 16-SOIC affect substitution?

A: Yes. The SN65C1167ENSR uses a 16-SOIC package while the SN75ALS171ADW uses 20-SOIC. Direct PCB substitution is not possible without layout modifications. The 16-SOIC package is physically smaller and has different pin spacing, requiring new footprint design and routing.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts (SN75ALS171DW, SN75ALS170ADW, SN75ALS170DW, and SN65C1167ENSR) are ROHS3 compliant with MSL rating of 1 (Unlimited), matching the compliance profile of the original SN75ALS171ADW.

Q: What supply voltage range should be used when substituting with SN65C1167ENSR?

A: The SN65C1167ENSR operates across 4.5V to 5.5V, which is wider than the SN75ALS171ADW specification of 4.75V to 5.25V. When substituting, maintain the original circuit supply voltage within the 4.75V to 5.25V range to ensure compatibility with both the original design intent and the substitute part's extended tolerance.

Q: Can the SN75ALS170ADW and SN75ALS170DW be used interchangeably?

A: Yes. Both parts are parametric equivalents with identical electrical specifications and 20-SOIC packaging. The difference in part number suffix (ADW vs. DW) reflects packaging tube designation but does not affect electrical performance or pin configuration.