OPA121KUG4 Equivalent & Substitute Parts

Part Overview

The OPA121KUG4 is a general-purpose operational amplifier manufactured by Texas Instruments, housed in an 8-SOIC surface mount package. This device is classified as a Difet® series amplifier with a single circuit configuration. The OPA121KUG4 is currently discontinued at DiGi Electronics, necessitating identification of equivalent substitute components for ongoing design requirements and production needs. Substitute parts must maintain compatibility with the original electrical specifications and mechanical form factor while offering active product status and continued availability.

Substiute Parts

OPA121KUG4

Texas InstrumentsIn Stock: 1095OPA121KUG4 Datasheet

Current PartRFQ

AD825ARZ

Analog Devices Inc.In Stock: 3588AD825ARZ Datasheet

MFR RecommendedRFQ

AD825ARZ-REEL

Analog Devices Inc.In Stock: 3680AD825ARZ-REEL Datasheet

MFR RecommendedRFQ

AD825ARZ-REEL7

Analog Devices Inc.In Stock: 18187AD825ARZ-REEL7 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the OPA121KUG4 are identified based on the following critical parameters that determine functional and mechanical compatibility:

Mechanical Compatibility:

• Package type: 8-SOIC (0.154", 3.90mm Width)
• Mounting type: Surface Mount
• Pin count and footprint equivalence

Electrical Compatibility:

• Voltage supply span: 10 V minimum to 36 V maximum
• Single circuit configuration
• 8-pin SOIC package format

Regulatory Compliance:

• RoHS3 compliance
• REACH unaffected status
• ECCN EAR99 classification

The substitute parts identified (AD825ARZ, AD825ARZ-REEL, and AD825ARZ-REEL7) share identical mechanical packaging and supply voltage specifications with the OPA121KUG4. All substitute parts are manufactured by Analog Devices Inc. and maintain active product status with current availability. The primary distinction between substitute options relates to packaging format (Tube versus Cut Tape & Digi-Reel®) and inventory levels, not electrical performance parameters.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The OPA121KUG4 is discontinued at DiGi Electronics, making the AD825ARZ series the appropriate substitute selection. All three AD825 variants (AD825ARZ, AD825ARZ-REEL, AD825ARZ-REEL7) maintain active product status with Analog Devices Inc., ensuring long-term availability and continued manufacturing support.

Compliance and Certification: All substitute parts maintain ROHS3 compliance and REACH unaffected status, matching the regulatory requirements of the original OPA121KUG4. The ECCN classification (EAR99) remains consistent across all parts.

Packaging Format Selection:

• AD825ARZ: Supplied in Tube packaging format
• AD825ARZ-REEL: Supplied in Cut Tape (CT) & Digi-Reel® format
• AD825ARZ-REEL7: Supplied in Cut Tape (CT) & Digi-Reel® format

Selection between these three variants depends on procurement requirements and assembly process specifications. The electrical and mechanical specifications are identical across all three part numbers.

Moisture Sensitivity: The substitute parts feature MSL 1 (Unlimited) rating, providing superior moisture tolerance compared to the OPA121KUG4 MSL 3 (168 Hours) rating. This represents an improvement in handling and storage flexibility.

Operating Temperature Range: The AD825 series supports an extended operating temperature range of -40°C to 85°C, compared to the OPA121KUG4 range of 0°C to 70°C. This extended range accommodates broader application environments.

Frequently Asked Questions (FAQ)

Q: Can the AD825ARZ series directly replace the OPA121KUG4 in existing designs?

A: The AD825ARZ series shares identical mechanical packaging (8-SOIC) and supply voltage specifications (10 V to 36 V) with the OPA121KUG4. Both devices are single-circuit operational amplifiers in surface mount configuration. Direct pin-for-pin substitution is supported from a mechanical and power supply perspective.

Q: What are the differences between AD825ARZ, AD825ARZ-REEL, and AD825ARZ-REEL7?

A: These three part numbers represent the same device with different packaging and delivery formats. AD825ARZ is supplied in Tube packaging. AD825ARZ-REEL and AD825ARZ-REEL7 are supplied in Cut Tape (CT) & Digi-Reel® format. The electrical specifications and 8-SOIC package dimensions are identical across all three variants. Selection depends on procurement and assembly process requirements.

Q: Are there electrical performance differences between the OPA121KUG4 and AD825ARZ?

A: The AD825ARZ exhibits higher performance specifications in several parameters: slew rate of 140 V/µs versus 2 V/µs, gain bandwidth product of 26 MHz versus 2 MHz, and output current capability of 50 mA versus 10 mA. The AD825ARZ is classified as a J-FET amplifier, while the OPA121KUG4 is a general-purpose Difet® amplifier. These differences indicate the AD825ARZ is a higher-performance device suitable for applications requiring faster response and greater output drive capability.

Q: What is the moisture sensitivity difference between these parts?

A: The OPA121KUG4 has MSL 3 rating (168 hours maximum floor life after moisture exposure). The AD825ARZ series has MSL 1 rating (unlimited floor life). MSL 1 provides superior moisture tolerance and more flexible handling and storage conditions without time-based constraints.

Q: Which AD825 variant should be selected for high-volume production?

A: AD825ARZ-REEL7 offers the highest inventory availability (18,103 pieces) among the three variants, making it the preferred choice for high-volume production requirements. AD825ARZ-REEL provides an alternative with 3,650 pieces in stock. Selection should align with assembly equipment specifications and procurement lead time requirements.

Q: Are all substitute parts RoHS3 compliant?

A: Yes, the OPA121KUG4 and all three AD825 variants are ROHS3 compliant and REACH unaffected. All parts carry the same ECCN classification (EAR99) and HTSUS code (8542.33.0001).

Q: What is the operating temperature range difference?

A: The OPA121KUG4 operates from 0°C to 70°C. The AD825ARZ series operates from -40°C to 85°C. The extended range of the AD825 series accommodates applications requiring operation in wider temperature environments, including industrial and automotive applications with lower temperature requirements.