LM324AN/PB Equivalent & Substitute Parts

Part Overview

The LM324AN/PB is a general-purpose operational amplifier featuring four independent circuits in a 14-DIP package. Manufactured by Texas Instruments under the LinCMOS™ series, this component is classified as obsolete, necessitating identification of equivalent alternatives for ongoing design support and procurement. The LM324AN/PB operates across a wide supply voltage range (3V to 32V) and maintains stable performance in industrial and commercial temperature environments (0°C to 70°C). Due to its obsolete status, equivalent substitute parts with matching electrical and mechanical specifications are essential for system continuity and component sourcing.

Substiute Parts

LM324AN/PB

Texas InstrumentsIn Stock: 761LM324AN/PB Datasheet

Current PartRFQ

LM324AN

STMicroelectronicsIn Stock: 55428LM324AN Datasheet

DirectRFQ

LM324AN/NOPB

Texas InstrumentsIn Stock: 2546LM324AN/NOPB Datasheet

DirectRFQ

KA324A

Fairchild SemiconductorIn Stock: 1409KA324A Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM324AN/PB are qualified based on strict alignment with the following electrical and mechanical criteria:

Primary Substitution Criteria:

• Four independent operational amplifier circuits
• General-purpose amplifier classification
• 1 MHz gain bandwidth product
• Supply voltage range: 3V to 32V minimum
• Output current capability: 40 mA per channel
• 14-DIP through-hole package (0.300", 7.62mm)
• Operating temperature range: 0°C to 70°C
• RoHS3 compliance and MSL Level 1 rating

Substitution Groups:

Group 1: Direct Functional Equivalents (Active Status) Parts meeting all electrical specifications with current product availability and active manufacturing status.

Group 2: Electrical Equivalents (Obsolete Status) Parts meeting all electrical specifications but with obsolete product status, suitable for legacy system maintenance.

Group 3: Manufacturer-Recommended Alternatives Parts designated by original manufacturers as functional alternatives with minor parameter variations within acceptable tolerance.

Parameter Comparison

Engineering Selection Recommendations

LM324AN/NOPB (Texas Instruments) — Preferred Primary Substitute

The LM324AN/NOPB is the recommended substitute for new designs and system updates. This part maintains identical electrical specifications to the LM324AN/PB, including 1 MHz gain bandwidth product, 45 nA input bias current, and 32V maximum supply voltage. Critically, the LM324AN/NOPB carries active product status with current manufacturing support, ensuring long-term availability and supply chain stability. The part is packaged in tube format and maintains full ROHS3 compliance and MSL Level 1 rating. Texas Instruments continues to support this variant, making it suitable for both legacy system maintenance and new production.

LM324AN (STMicroelectronics) — Secondary Substitute

The STMicroelectronics LM324AN provides functional equivalence with all critical electrical parameters aligned to the LM324AN/PB. This part features superior input bias current performance (20 nA versus 45 nA), reducing input offset drift in precision applications. However, the maximum supply voltage is limited to 30V compared to 32V on the original part. The STMicroelectronics variant carries obsolete product status but maintains substantial inventory availability (55,339 units in stock). This part is suitable for legacy system support where supply voltage does not exceed 30V.

KA324A (Fairchild Semiconductor) — Alternative Substitute

The Fairchild KA324A is designated as a manufacturer-recommended alternative with active product status. This part meets all critical electrical specifications including 4-circuit configuration, 40 mA output current per channel, and 32V maximum supply voltage. The KA324A demonstrates superior input offset voltage performance (1.5 mV versus 2 mV). Moisture sensitivity level is vendor-undefined, requiring verification against specific environmental requirements. This part is suitable for applications where Fairchild component qualification is acceptable.

Frequently Asked Questions (FAQ)

Q: Can the LM324AN/NOPB directly replace the LM324AN/PB in existing PCB designs?

A: Yes. Both parts share identical electrical specifications (1 MHz gain bandwidth, 45 nA input bias current, 32V maximum supply) and the same 14-DIP through-hole package footprint (0.300", 7.62mm). No PCB layout modifications are required. The primary difference is packaging format (tube versus bulk) and active versus obsolete product status.

Q: What is the significance of the STMicroelectronics LM324AN having 20 nA input bias current versus 45 nA on the original part?

A: Lower input bias current reduces input offset drift and improves precision in high-impedance signal conditioning applications. However, this parameter difference does not prevent substitution. The STMicroelectronics part remains functionally equivalent for general-purpose amplifier applications. Verify that your circuit design does not depend on the specific 45 nA bias current value.

Q: Why does the STMicroelectronics LM324AN have a 30V maximum supply limit while the original supports 32V?

A: This represents a minor specification variance between manufacturers. If your design operates at supply voltages between 30V and 32V, the STMicroelectronics part is not suitable. The LM324AN/NOPB (Texas Instruments) or KA324A (Fairchild) maintain the full 32V rating and are recommended for such applications.

Q: Is the KA324A suitable for applications requiring RoHS3 compliance?

A: The KA324A carries REACH Unaffected status and meets general environmental standards. However, RoHS3 compliance status is not explicitly documented in the provided specifications. If RoHS3 compliance is a mandatory requirement, the LM324AN/NOPB or STMicroelectronics LM324AN are confirmed compliant alternatives.

Q: Can I use the LM324AN/NOPB in tube packaging for automated pick-and-place assembly?

A: Tube packaging is designed for manual handling and tape-and-reel feeder systems. For high-speed automated assembly, verify that your pick-and-place equipment supports tube-fed components. If your assembly process requires tape-and-reel format, contact the distributor for alternative packaging options or consider the bulk-packaged variants.

Q: What is the difference between LM324AN and LM324AN/PB?

A: The LM324AN/PB designation includes "/PB" indicating lead-free (Pb-free) RoHS compliance. The base LM324AN part number may reference either leaded or lead-free variants depending on manufacturer and production date. Both the LM324AN (STMicroelectronics) and LM324AN/NOPB (Texas Instruments) are lead-free compliant alternatives.

Q: Are all four operational amplifier circuits within a single package guaranteed to have identical performance?

A: Yes. The LM324 architecture integrates four independent amplifier circuits on a single die. All electrical specifications (gain bandwidth, input bias current, output current) apply to each circuit. However, minor parametric variations between individual circuits may occur within the specified tolerance bands. Refer to the manufacturer datasheet for detailed matching specifications if precision matching between circuits is required.