BUF634U Equivalent & Substitute Parts

Part Overview

The BUF634U is a buffer amplifier integrated circuit manufactured by Texas Instruments, housed in an 8-SOIC surface mount package. This device functions as a single-circuit buffer amplifier with high slew rate and bandwidth characteristics suitable for signal conditioning applications. The BUF634U carries a "Not For New Designs" product status, indicating that Texas Instruments has discontinued active development and support for this component. Identifying equivalent and substitute parts is necessary for ongoing production support, design updates, and long-term supply chain management.

Substiute Parts

BUF634U

Texas InstrumentsIn Stock: 15461BUF634U Datasheet

Current PartRFQ

BUF634AIDR

Texas InstrumentsIn Stock: 37653BUF634AIDR Datasheet

MFR RecommendedRFQ

INA117KU

Texas InstrumentsIn Stock: 1496INA117KU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BUF634U is determined by compatibility across the following critical parameters: package type (8-SOIC surface mount), supply voltage range (4.5V to 36V minimum overlap), output current capability (250 mA per channel), and operating temperature range (-40°C to 85°C minimum). The substitute parts identified are both manufactured by Texas Instruments and share the same physical package footprint.

BUF634AIDR qualifies as a substitute based on identical package geometry, overlapping supply voltage specifications (4.5V to 36V), matching output current rating (250 mA), and compatible operating temperature range (-40°C to 125°C, which exceeds the original specification). This part is classified as Active product status.

INA117KU qualifies as a substitute based on identical package geometry and overlapping supply voltage range (10V to 36V minimum). However, this part exhibits reduced output current capability (20 mA versus 250 mA) and significantly lower bandwidth (200 kHz versus 180 MHz), making it suitable only for applications with relaxed performance requirements.

Parameter Comparison

Engineering Selection Recommendations

BUF634AIDR is the primary substitute for the BUF634U. Both parts are manufactured by Texas Instruments and share identical package specifications. The BUF634AIDR maintains full electrical compatibility with the original part across all critical parameters: supply voltage range (4.5V to 36V), output current (250 mA), and operating temperature (-40°C to 125°C). The BUF634AIDR is classified as Active product status, ensuring continued availability and manufacturer support. This part is ROHS3 compliant and carries REACH Unaffected certification, matching the compliance profile of the original component.

INA117KU is a secondary substitute suitable only for applications where reduced performance specifications are acceptable. The INA117KU exhibits significantly lower bandwidth (200 kHz versus 180 MHz) and reduced output current capability (20 mA versus 250 mA). Additionally, the INA117KU requires a minimum supply voltage of 10V, which may not be compatible with systems designed for the BUF634U's 4.5V minimum specification. The INA117KU is classified as Active product status and maintains ROHS3 compliance.

For new designs or production transitions, BUF634AIDR is the recommended substitute. The INA117KU should be considered only when application requirements permit significant reductions in bandwidth and output current.

Frequently Asked Questions (FAQ)

Q: Can BUF634AIDR be used as a direct replacement for BUF634U in existing designs?

A: BUF634AIDR shares the same 8-SOIC package footprint and pin configuration as BUF634U. Both parts operate across the 4.5V to 36V supply range and deliver 250 mA output current. The primary differences are improved slew rate (3750 V/µs versus 2000 V/µs) and extended operating temperature range (-40°C to 125°C versus -40°C to 85°C). These differences represent performance enhancements rather than limitations, making BUF634AIDR suitable for direct substitution in PCB layouts designed for BUF634U.

Q: What are the key differences between BUF634AIDR and INA117KU?

A: BUF634AIDR is classified as a general-purpose amplifier with push-pull output, while INA117KU is a differential amplifier. BUF634AIDR maintains the 250 mA output current specification of the original BUF634U, whereas INA117KU is limited to 20 mA. BUF634AIDR operates with a minimum supply voltage of 4.5V, while INA117KU requires a minimum of 10V. BUF634AIDR bandwidth is 210 MHz compared to INA117KU's 200 kHz. These differences make BUF634AIDR the superior choice for applications requiring high-speed buffering.

Q: Is INA117KU compatible with BUF634U applications?

A: INA117KU is not recommended as a direct substitute for BUF634U in high-speed applications. The 200 kHz bandwidth of INA117KU is approximately 900 times lower than the BUF634U's 180 MHz specification. The 20 mA output current limit is 12.5 times lower than the 250 mA capability of BUF634U. INA117KU is suitable only for low-frequency differential signal conditioning where reduced bandwidth and output current are acceptable.

Q: Are all three parts (BUF634U, BUF634AIDR, INA117KU) available in the same packaging options?

A: All three parts are housed in 8-SOIC surface mount packages with identical physical dimensions (0.154" width, 3.90mm). BUF634U and INA117KU are supplied in Tube packaging, while BUF634AIDR is available in Cut Tape and Digi-Reel packaging options. The identical package geometry ensures PCB layout compatibility across all three parts.

Q: What is the product status significance for component selection?

A: BUF634U carries "Not For New Designs" status, indicating Texas Instruments has discontinued active development. BUF634AIDR and INA117KU are both classified as Active, meaning they receive ongoing manufacturer support, quality assurance, and guaranteed long-term availability. For production designs requiring sustained component supply, Active-status parts are preferred.

Q: Do all substitute parts meet the same compliance requirements as BUF634U?

A: Yes. BUF634U, BUF634AIDR, and INA117KU are all ROHS3 compliant and REACH unaffected. All three parts carry EAR99 ECCN classification. Moisture sensitivity levels differ: BUF634U and INA117KU are MSL 3 (168 Hours), while BUF634AIDR is MSL 2 (1 Year), indicating improved moisture tolerance for BUF634AIDR.