SN65LBC179AP Equivalent & Substitute Parts

Part Overview

The SN65LBC179AP is a 1/1 transceiver IC for RS422 and RS485 communication protocols, manufactured by Texas Instruments in an 8-DIP through-hole package. This part is classified as obsolete, making equivalent substitutes necessary for new designs and ongoing production support. The SN65LBC179AP delivers 30 Mbps data rate performance with full-duplex capability and operates across the industrial temperature range of -40°C to 85°C.

Substiute Parts

SN65LBC179AP

Texas InstrumentsIn Stock: 3933SN65LBC179AP Datasheet

Current PartRFQ

SN65LBC179ADR

Texas InstrumentsIn Stock: 7730SN65LBC179ADR Datasheet

MFR RecommendedRFQ

MAX488ECPA+

Analog Devices Inc./Maxim IntegratedIn Stock: 3982MAX488ECPA+ Datasheet

MFR RecommendedRFQ

MAX488EEPA+

Analog Devices Inc./Maxim IntegratedIn Stock: 1883MAX488EEPA+ Datasheet

MFR RecommendedRFQ

MAX490ECPA+

Analog Devices Inc./Maxim IntegratedIn Stock: 3688MAX490ECPA+ Datasheet

MFR RecommendedRFQ

MAX490EEPA+

Analog Devices Inc./Maxim IntegratedIn Stock: 1674MAX490EEPA+ Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SN65LBC179AP is determined by the following critical parameters:

Primary Compatibility Criteria:

• Protocol support: RS422 and RS485
• Configuration: 1/1 driver/receiver
• Duplex mode: Full
• Supply voltage range: 4.75V ~ 5.25V
• RoHS3 compliance

Secondary Considerations:

• Data rate performance (minimum 30 Mbps required for direct replacement)
• Operating temperature range (-40°C to 85°C preferred for industrial applications)
• Receiver hysteresis specification (50 mV baseline)
• Package type (through-hole 8-DIP preferred; surface-mount alternatives available)

Substitutes are grouped into two categories: direct pin-compatible replacements in 8-DIP packaging, and functional equivalents with different package types. The SN65LBC179ADR provides identical electrical performance in surface-mount 8-SOIC packaging. The MAX488 and MAX490 series from Analog Devices offer functional equivalence with trade-offs in data rate and receiver hysteresis specifications.

Parameter Comparison

Engineering Selection Recommendations

SN65LBC179ADR is the primary substitute for the SN65LBC179AP. Both parts share identical electrical specifications, including 30 Mbps data rate, 50 mV receiver hysteresis, and -40°C to 85°C operating temperature range. The SN65LBC179ADR is manufactured by Texas Instruments with active product status and ROHS3 compliance. The only difference is packaging: SN65LBC179ADR uses surface-mount 8-SOIC instead of through-hole 8-DIP. This substitute is suitable for new PCB designs or rework applications where surface-mount technology is preferred.

MAX488EEPA+ provides functional equivalence with full industrial temperature support (-40°C to 85°C) and active product status. However, this part operates at 250 kbps data rate, significantly lower than the SN65LBC179AP's 30 Mbps capability. The MAX488EEPA+ is appropriate only for low-speed RS422/RS485 applications where bandwidth requirements do not exceed 250 kbps.

MAX490EEPA+ offers intermediate data rate performance at 2.5 Mbps with full industrial temperature range (-40°C to 85°C) and active product status. This substitute is suitable for applications requiring higher bandwidth than MAX488 but lower than the original SN65LBC179AP specification.

MAX488ECPA+ and MAX490ECPA+ are restricted to commercial temperature range (0°C to 70°C) and are not suitable for industrial or extended-temperature applications.

All substitute parts maintain ROHS3 compliance and 4.75V to 5.25V supply voltage compatibility with the original part.

Frequently Asked Questions (FAQ)

Q: Can I use SN65LBC179ADR as a direct replacement for SN65LBC179AP?

A: Yes, electrically and functionally. Both parts are manufactured by Texas Instruments with identical specifications for protocol, data rate, hysteresis, supply voltage, and operating temperature. The difference is packaging: SN65LBC179ADR is surface-mount 8-SOIC while SN65LBC179AP is through-hole 8-DIP. PCB layout and assembly process must accommodate the different package type.

Q: Why do MAX488 and MAX490 parts have lower data rates than the SN65LBC179AP?

A: The MAX488 series is specified for 250 kbps operation, and the MAX490 series for 2.5 Mbps. These are design specifications from Analog Devices and represent different performance tiers within their transceiver product line. The SN65LBC179AP operates at 30 Mbps, making it suitable for higher-speed applications.

Q: Are MAX488ECPA+ and MAX490ECPA+ suitable for industrial applications?

A: No. These parts are rated for 0°C to 70°C commercial temperature range only. Industrial applications requiring -40°C to 85°C operation must use MAX488EEPA+ or MAX490EEPA+, which include the extended temperature specification.

Q: What is the significance of receiver hysteresis differences?

A: The SN65LBC179AP and SN65LBC179ADR specify 50 mV receiver hysteresis, while MAX488 and MAX490 series specify 70 mV. Hysteresis affects noise immunity and switching threshold behavior. The 50 mV specification provides tighter threshold control, while 70 mV offers greater noise margin. Selection depends on signal integrity requirements in the specific application.

Q: Can I use MAX490EEPA+ in place of SN65LBC179AP?

A: Functionally, yes, with limitations. Both support RS422/RS485 protocols, 1/1 driver/receiver configuration, full-duplex operation, and -40°C to 85°C temperature range. However, MAX490EEPA+ is limited to 2.5 Mbps data rate compared to SN65LBC179AP's 30 Mbps. Use this substitute only if your application bandwidth requirement does not exceed 2.5 Mbps.

Q: What compliance certifications apply to all substitute parts?

A: All listed substitutes maintain ROHS3 compliance and REACH Unaffected status, matching the original SN65LBC179AP specifications. All parts are classified under HTSUS code 8542.39.0001.