MAX478CPA Equivalent & Substitute Parts

Part Overview

The MAX478CPA is a general-purpose operational amplifier featuring two independent circuits in an 8-PDIP through-hole package, manufactured by Analog Devices Inc./Maxim Integrated. This device is classified as obsolete, indicating discontinued production and limited availability for new designs. The part operates across a wide supply voltage range of 3V to 30V with low input bias current and moderate slew rate characteristics suitable for general analog signal processing applications. Due to its obsolete status, identifying functionally equivalent active alternatives is essential for design continuity and long-term component sourcing.

Substiute Parts

MAX478CPA

Analog Devices Inc./Maxim IntegratedIn Stock: 2020MAX478CPA Datasheet

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LT1178IN8#PBF

Analog Devices Inc.In Stock: 2356LT1178IN8#PBF Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the MAX478CPA is determined by strict alignment of the following critical parameters:

Functional Equivalence Criteria:

• Dual-channel general-purpose operational amplifier architecture
• 8-PDIP through-hole package format (0.300", 7.62mm)
• Slew rate of 0.04 V/µs
• Gain bandwidth product of 85 kHz
• Input bias current of 3 nA
• Supply voltage range compatibility (minimum 3V to maximum 30V overlap)

Compliance & Status Considerations:

• Active product status preferred for long-term availability
• RoHS compliance status for regulatory alignment
• Operating temperature range suitability for target application environment

The LT1178IN8#PBF qualifies as a direct substitute based on matching functional specifications, identical package format, and active product status. This part maintains electrical parameter equivalence while offering improved regulatory compliance and extended temperature operation.

Parameter Comparison

Engineering Selection Recommendations

LT1178IN8#PBF as Primary Substitute:

The LT1178IN8#PBF is the qualified substitute for MAX478CPA applications based on the following engineering factors:

1. Functional Compatibility: Identical core amplifier specifications (slew rate, gain bandwidth product, input bias current) ensure direct functional replacement in existing circuit designs.

2. Package Compatibility: Both devices utilize the 8-DIP through-hole package format, enabling direct PCB footprint compatibility without layout modifications.

3. Product Status Advantage: Active product status of LT1178IN8#PBF ensures continued availability and manufacturing support, addressing the obsolescence risk of MAX478CPA.

4. Regulatory Compliance: ROHS3 compliance of LT1178IN8#PBF aligns with current regulatory requirements, whereas MAX478CPA is RoHS non-compliant.

5. Operating Temperature Extension: Extended temperature range (-40°C to 85°C) of LT1178IN8#PBF provides broader application flexibility compared to MAX478CPA (0°C to 70°C).

Parameter Variance Considerations:

• Voltage - Input Offset: LT1178IN8#PBF specifies 100 µV versus MAX478CPA at 50 µV. This 2× difference remains within acceptable tolerance for general-purpose amplifier applications.
• Current - Supply: LT1178IN8#PBF draws 17 µA per channel versus 13 µA for MAX478CPA. This 4 µA increase per channel is negligible in most power budget calculations.
• Voltage - Supply Span (Min): LT1178IN8#PBF requires minimum 5V versus 3V for MAX478CPA. Circuit designs must verify 5V minimum supply availability.

Frequently Asked Questions (FAQ)

Q1: Can LT1178IN8#PBF directly replace MAX478CPA in existing designs without circuit modification?

A: Direct PCB-level replacement is possible due to identical 8-DIP package format and matching pin configuration. However, circuit designs operating below 5V supply voltage require modification, as LT1178IN8#PBF specifies a 5V minimum supply versus 3V for MAX478CPA. Verify input offset voltage tolerance (100 µV vs. 50 µV) for precision applications.

Q2: What are the key electrical differences between these parts?

A: The primary differences are: (1) Input offset voltage is doubled (100 µV vs. 50 µV), (2) Supply current increases by 4 µA per channel, and (3) minimum supply voltage requirement increases from 3V to 5V. Slew rate, gain bandwidth product, and input bias current remain identical.

Q3: Is the LT1178IN8#PBF suitable for low-voltage applications below 5V?

A: No. LT1178IN8#PBF specifies a minimum supply voltage of 5V. Applications requiring operation below 5V must retain MAX478CPA or identify alternative parts with lower minimum supply voltage specifications.

Q4: What is the impact of the extended operating temperature range of LT1178IN8#PBF?

A: LT1178IN8#PBF operates from -40°C to 85°C, compared to MAX478CPA at 0°C to 70°C. This extension provides compatibility with industrial and automotive temperature environments. Applications limited to 0°C to 70°C operation experience no functional impact.

Q5: Does RoHS compliance of LT1178IN8#PBF affect circuit performance?

A: RoHS compliance is a manufacturing and material specification, not a functional performance parameter. ROHS3 compliance of LT1178IN8#PBF indicates adherence to hazardous substance restrictions and does not alter electrical characteristics or circuit behavior.

Q6: Are there packaging differences between MAX478CPA and LT1178IN8#PBF?

A: Both parts use 8-DIP through-hole packages with identical 0.300" (7.62mm) body width. Packaging format is fully compatible. LT1178IN8#PBF is supplied in tube packaging, whereas MAX478CPA packaging format is not specified in available data.