LP324N Equivalent & Substitute Parts

Part Overview

The LP324N is a general-purpose operational amplifier manufactured by Texas Instruments, housed in a 14-DIP through-hole package. This device integrates four independent amplifier circuits on a single integrated circuit and operates across a wide supply voltage range of 3V to 32V. The LP324N is classified as Last Time Buy, indicating that Texas Instruments has discontinued this product line. Finding equivalent and substitute parts is necessary to maintain design continuity, ensure long-term component availability, and support ongoing production requirements for applications utilizing this operational amplifier.

Substiute Parts

LP324N

Texas InstrumentsIn Stock: 4066LP324N Datasheet

Current PartRFQ

LP324DR

Texas InstrumentsIn Stock: 18378LP324DR Datasheet

MFR RecommendedRFQ

LM324AN

STMicroelectronicsIn Stock: 55428LM324AN Datasheet

MFR RecommendedRFQ

LM324AN/NOPB

Texas InstrumentsIn Stock: 2546LM324AN/NOPB Datasheet

MFR RecommendedRFQ

LM324N

IntersilIn Stock: 324627LM324N Datasheet

MFR RecommendedRFQ

LM324N/NOPB

Texas InstrumentsIn Stock: 43700LM324N/NOPB Datasheet

MFR RecommendedRFQ

LP324N/NOPB

Texas InstrumentsIn Stock: 1611LP324N/NOPB Datasheet

MFR RecommendedRFQ

KA324A

Fairchild SemiconductorIn Stock: 1409KA324A Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LP324N is determined by strict alignment of electrical and mechanical parameters. The following criteria establish valid substitute relationships:

Primary Substitution Criteria:

• Amplifier Type: General Purpose (4-circuit configuration)
• Number of Circuits: 4 independent amplifiers
• Supply Voltage Range: Minimum 3V, Maximum 32V
• Operating Temperature Range: 0°C to 70°C
• Package Type: 14-DIP through-hole mounting (0.300", 7.62mm)
• RoHS Compliance: ROHS3 Compliant preferred

Secondary Electrical Parameters (Performance Compatibility):

• Slew Rate: 0.05V/µs or higher
• Gain Bandwidth Product: 100 kHz or higher
• Input Bias Current: 2 nA or lower
• Input Offset Voltage: 2 mV or lower
• Supply Current: 150µA or lower
• Output Current per Channel: 10 mA or higher

Substitute parts are grouped into two categories: Direct Package Equivalents (14-DIP through-hole) and Package Alternatives (14-SOIC surface mount). Direct package equivalents maintain identical mechanical compatibility. Package alternatives provide electrical equivalence but require PCB redesign for surface-mount implementation.

Parameter Comparison

Engineering Selection Recommendations

Tier 1 - Direct Electrical and Mechanical Equivalents (Recommended):

LP324N/NOPB (Texas Instruments) is the primary substitute. This part maintains identical electrical specifications (Slew Rate 0.05V/µs, Gain Bandwidth Product 100 kHz, Input Bias Current 2 nA, Supply Current 150µA) and mechanical compatibility (14-DIP through-hole package). Product status is Active with ROHS3 compliance. This part is functionally interchangeable with no circuit modifications required.

LM324N/NOPB (Texas Instruments) is a secondary direct equivalent. This part shares the same 14-DIP through-hole package and supply voltage range. However, it exhibits higher input bias current (45 nA versus 2 nA) and increased supply current (1.5mA versus 150µA). Product status is Active with ROHS3 compliance. Selection of this part is appropriate when higher bias current and supply current are acceptable within the application circuit design.

Tier 2 - Package Alternative (Surface Mount):

LP324DR (Texas Instruments) provides electrical equivalence with identical performance specifications to LP324N but in a 14-SOIC surface-mount package. This substitution requires PCB redesign to accommodate surface-mount footprint. Product status is Active with ROHS3 compliance. This option is suitable for new PCB designs or redesigns where surface-mount technology is preferred.

Tier 3 - Cross-Manufacturer Alternatives:

KA324A (Fairchild Semiconductor) is a cross-manufacturer substitute in 14-DIP through-hole package. This part meets the supply voltage range and operating temperature requirements. Input offset voltage is superior (1.5 mV versus 2 mV). However, input bias current is higher (40 nA versus 2 nA) and supply current is significantly higher (1.5mA versus 150µA). Product status is Active. RoHS compliance status is not specified. This option is suitable when cross-manufacturer sourcing is required and higher bias/supply currents are acceptable.

Selection Priority Based on Product Status and Compliance:

1. LP324N/NOPB (Active, ROHS3, identical specifications)
2. LM324N/NOPB (Active, ROHS3, higher bias/supply current)
3. LP324DR (Active, ROHS3, surface-mount alternative)
4. KA324A (Active, RoHS status undefined, cross-manufacturer)

Frequently Asked Questions (FAQ)

Q1: Can LP324N/NOPB be used as a direct replacement for LP324N without circuit modifications?

A: Yes. LP324N/NOPB is electrically and mechanically identical to LP324N. Both parts share the same 14-DIP through-hole package, identical slew rate (0.05V/µs), gain bandwidth product (100 kHz), input bias current (2 nA), and supply current (150µA). No circuit modifications are required. The /NOPB suffix indicates lead-free (Pb-free) compliance.

Q2: What is the difference between LP324N and LM324N/NOPB?

A: Both parts use the 14-DIP through-hole package and operate across 3V to 32V supply range. The primary differences are: LM324N/NOPB has higher input bias current (45 nA versus 2 nA), higher supply current (1.5mA versus 150µA), and higher gain bandwidth product (1 MHz versus 100 kHz). LM324N/NOPB is suitable for applications where higher bandwidth and output current are required, but it consumes more power.

Q3: Can LP324DR replace LP324N in an existing PCB design?

A: No. LP324DR uses a 14-SOIC surface-mount package, while LP324N uses a 14-DIP through-hole package. These packages have different footprints and cannot be used interchangeably on the same PCB without redesign. LP324DR is suitable only for new PCB designs or PCB redesigns that accommodate surface-mount components.

Q4: Is KA324A a suitable substitute for LP324N?

A: KA324A is a cross-manufacturer alternative that shares the 14-DIP through-hole package and supply voltage range. However, it has higher input bias current (40 nA versus 2 nA) and significantly higher supply current (1.5mA versus 150µA). KA324A is suitable when cross-manufacturer sourcing is necessary and the application circuit can tolerate higher bias and supply currents. Verify circuit performance before implementation.

Q5: What does ROHS3 compliance mean for these operational amplifiers?

A: ROHS3 compliance indicates that the part meets the Restriction of Hazardous Substances Directive 3 (RoHS 3), which restricts the use of specific hazardous materials including lead, cadmium, mercury, and certain brominated flame retardants. All recommended substitutes (LP324N/NOPB, LM324N/NOPB, LP324DR) are ROHS3 compliant, ensuring regulatory compliance for applications subject to RoHS requirements.

Q6: Why is LP324N classified as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued the LP324N product line and will no longer manufacture this part after a specified date. Existing inventory will be sold until depletion. Customers requiring this functionality should transition to active product alternatives such as LP324N/NOPB, LM324N/NOPB, or LP324DR to ensure long-term component availability and supply chain continuity.

Q7: Which substitute part has the lowest power consumption?

A: LP324DR has the lowest supply current at 85µA (per 4 channels), compared to LP324N at 150µA. However, LP324DR requires surface-mount PCB implementation. Among through-hole 14-DIP packages, LP324N and LP324N/NOPB both consume 150µA, which is lower than LM324N/NOPB and KA324A at 1.5mA.

Q8: Are there any inventory considerations when selecting a substitute?

A: Yes. Current inventory levels vary significantly: LM324N/NOPB has the highest inventory (43,654 pcs), followed by LP324DR (18,309 pcs), LP324N (3,987 pcs), LM324AN/NOPB (2,514 pcs), LP324N/NOPB (1,520 pcs), and KA324A (1,300 pcs). For high-volume production requirements, LM324N/NOPB or LP324DR offer greater availability. For low-volume applications, all options maintain adequate stock levels.