BUF634T Equivalent & Substitute Parts

Part Overview

The BUF634T is a buffer amplifier integrated circuit manufactured by Texas Instruments, housed in a TO-220-5 through-hole package. This device functions as a single-circuit buffer amplifier with high slew rate and bandwidth characteristics suitable for signal conditioning and impedance matching applications. The BUF634T carries a "Not For New Designs" product status, indicating that Texas Instruments no longer recommends this component for new circuit development. Identifying equivalent and substitute parts is necessary to support legacy system maintenance, repair operations, and design transitions to actively supported alternatives.

Substiute Parts

BUF634T

Texas InstrumentsIn Stock: 4183BUF634T Datasheet

Current PartRFQ

BUF634AIDR

Texas InstrumentsIn Stock: 37653BUF634AIDR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the BUF634T is determined by compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Supply voltage range: Substitute must support 4.5 V to 36 V operation
• Output current capability: Minimum 250 mA per channel required
• Amplifier function: Buffer or general-purpose amplifier topology
• Single-circuit configuration: One amplification stage per package

Mechanical & Environmental Criteria:

• Regulatory compliance: RoHS3 and REACH status alignment
• Operating temperature: Substitute must cover -40°C to 85°C minimum
• Base product number: BUF634 family designation indicates functional equivalence

Packaging Consideration: The BUF634T uses TO-220-5 through-hole packaging. Substitutes may employ alternative package types (such as 8-SOIC surface-mount) provided that the electrical specifications remain compatible and the application circuit topology permits package substitution.

The BUF634AIDR qualifies as a substitute based on matching supply voltage range, output current rating, single-circuit configuration, and regulatory compliance, despite differences in package type and amplifier classification.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Same PCB Layout): Direct substitution of BUF634T with BUF634AIDR is not feasible without PCB modification due to package incompatibility. The BUF634T uses TO-220-5 through-hole mounting, while BUF634AIDR employs 8-SOIC surface-mount packaging. Footprint, pin spacing, and mounting hole requirements differ fundamentally.

For New Circuit Design or PCB Redesign: The BUF634AIDR is the recommended substitute when PCB layout modification is permissible. This device carries "Active" product status from Texas Instruments, ensuring continued manufacturing support, availability, and technical documentation. The BUF634AIDR demonstrates superior electrical performance across multiple parameters: slew rate (3750 V/µs vs. 2000 V/µs), bandwidth (210 MHz vs. 180 MHz), input bias current (30 nA vs. 5 µA), and supply current (8.5 mA vs. 15 mA). Operating temperature range extends to 125°C, providing enhanced thermal margin. Both devices maintain identical supply voltage range (4.5 V to 36 V) and output current capability (250 mA), ensuring functional compatibility in the signal path.

Regulatory & Compliance Alignment: Both BUF634T and BUF634AIDR maintain ROHS3 compliance and REACH unaffected status, satisfying environmental and hazardous substance restrictions for industrial and commercial applications.

Frequently Asked Questions (FAQ)

Q: Can BUF634AIDR replace BUF634T without modifying the circuit board?

A: No. The BUF634T is packaged in TO-220-5 (through-hole), while BUF634AIDR uses 8-SOIC (surface-mount). PCB footprint, pin layout, and mounting method are incompatible. Direct socket substitution is not possible. PCB redesign is required to accommodate the different package type.

Q: What are the key electrical differences between BUF634T and BUF634AIDR?

A: Both devices share identical supply voltage range (4.5 V to 36 V) and output current rating (250 mA per channel). BUF634AIDR provides superior performance: slew rate increases from 2000 V/µs to 3750 V/µs, bandwidth increases from 180 MHz to 210 MHz, input bias current decreases from 5 µA to 30 nA, and supply current decreases from 15 mA to 8.5 mA. Operating temperature range extends from -40 to 85°C (BUF634T) to -40 to 125°C (BUF634AIDR).

Q: Why is BUF634T marked "Not For New Designs"?

A: This designation indicates that Texas Instruments has transitioned this component to end-of-life status and no longer recommends it for new circuit development. The BUF634AIDR represents the active, supported alternative within the BUF634 product family.

Q: Are both parts RoHS compliant?

A: Yes. Both BUF634T and BUF634AIDR are ROHS3 compliant and REACH unaffected, meeting environmental and hazardous substance regulations for commercial and industrial applications.

Q: If I need through-hole mounting, what are my options?

A: The BUF634T remains available in through-hole TO-220-5 packaging. However, given its "Not For New Designs" status, long-term availability cannot be guaranteed. For new designs requiring through-hole mounting, consult Texas Instruments documentation for alternative buffer amplifier products in through-hole packages, or consider surface-mount alternatives with appropriate PCB design modifications.

Q: What is the inventory status of these parts?

A: BUF634T inventory is 4092 pieces (new original, in stock). BUF634AIDR inventory is 37600 pieces (new original, in stock, cut tape and Digi-Reel packaging). The significantly higher BUF634AIDR inventory reflects its active product status.

Q: Can BUF634AIDR operate across the same supply voltage range as BUF634T?

A: Yes. Both devices operate across 4.5 V to 36 V supply voltage range, ensuring compatibility in applications requiring wide supply voltage tolerance.