LM1558H Equivalent & Substitute Parts

Part Overview

The LM1558H is a general-purpose operational amplifier manufactured by Texas Instruments, housed in a TO-99-8 metal can package. This device contains two independent amplifier circuits and is designed for applications requiring dual-channel amplification with moderate bandwidth and low input offset voltage. The LM1558H maintains active product status with 2163 units in current inventory.

Substitute parts are identified when equivalent functional performance can be achieved within the allowed electrical and mechanical parameters of the TO-99-8 package category, maintaining compatibility with through-hole mounting applications and the specified operating temperature range of -55°C to 125°C.

Substiute Parts

LM1558H

Texas InstrumentsIn Stock: 2187LM1558H Datasheet

Current PartRFQ

LF412MH/NOPB

National SemiconductorIn Stock: 2658LF412MH/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM1558H is determined by the following critical parameters:

Package Compatibility: Both the main part and substitute must use the TO-99-8 metal can package with through-hole mounting to ensure direct socket compatibility.

Circuit Configuration: The substitute must contain exactly two independent amplifier circuits to match the dual-channel architecture of the LM1558H.

Operating Temperature Range: The substitute must support the full -55°C to 125°C operating temperature range required for military and industrial applications.

Supply Voltage Compatibility: The substitute's supply voltage span must accommodate the 44 V specification of the LM1558H, or operate within a subset of this range if the application permits.

Electrical Performance: While substitutes may exhibit different slew rates, gain bandwidth products, input bias currents, and supply currents, these parameters must be suitable for the intended application. The input offset voltage and other DC characteristics must remain within acceptable limits for the circuit design.

The LF412MH/NOPB qualifies as a substitute based on matching package type, circuit count, temperature range, and supply voltage compatibility, despite differences in amplifier topology (J-FET versus bipolar) and dynamic performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (LM1558H): Select the LM1558H when the application requires the specified electrical characteristics, including the 0.5 V/µs slew rate and 1 MHz gain bandwidth product. This device is actively manufactured and maintains full inventory availability. ROHS3 compliance and MSL Level 1 rating support applications with standard moisture and environmental requirements.

Substitute Selection (LF412MH/NOPB): The LF412MH/NOPB serves as a substitute when enhanced dynamic performance is acceptable or required. The J-FET input topology provides significantly lower input bias current (50 pA versus 200 nA), making this device suitable for high-impedance signal sources. The 15 V/µs slew rate and 4 MHz gain bandwidth product enable faster signal processing. However, the maximum supply voltage of 40 V is lower than the LM1558H specification of 44 V; verify that the application supply voltage does not exceed 40 V before substitution.

Both devices maintain active product status, identical operating temperature ranges, and compatible TO-99-8 packaging. Selection between these parts depends on whether the application prioritizes the lower input bias current and higher bandwidth of the LF412MH/NOPB or the lower slew rate and higher supply voltage capability of the LM1558H.

Frequently Asked Questions (FAQ)

Q: Can the LF412MH/NOPB directly replace the LM1558H in an existing circuit?

A: Direct replacement is possible only if the application supply voltage does not exceed 40 V (the maximum rating of the LF412MH/NOPB). The TO-99-8 package pinout is identical, enabling socket-level substitution. However, the different amplifier topology (J-FET versus bipolar) and higher slew rate may affect circuit behavior in applications sensitive to input bias current or frequency response. Circuit validation is necessary to confirm functional equivalence.

Q: What is the primary difference between these two amplifiers?

A: The LM1558H uses a bipolar input stage with 200 nA input bias current and 0.5 V/µs slew rate. The LF412MH/NOPB uses a J-FET input stage with 50 pA input bias current and 15 V/µs slew rate. The J-FET topology is advantageous for high-impedance applications; the bipolar topology supports higher supply voltages.

Q: Are both parts available in the same package?

A: Yes. Both the LM1558H and LF412MH/NOPB are packaged in TO-99-8 metal can with through-hole mounting. Pin configuration is identical, supporting direct socket replacement.

Q: What is the supply voltage limitation for the LF412MH/NOPB?

A: The LF412MH/NOPB maximum supply voltage is 40 V. The LM1558H supports 44 V. If the application requires operation at 41 V to 44 V, the LM1558H must be used.

Q: Do both parts support the full -55°C to 125°C temperature range?

A: Yes. Both the LM1558H and LF412MH/NOPB are rated for -55°C to 125°C operation, supporting military and industrial temperature specifications.

Q: What compliance certifications apply to these parts?

A: The LM1558H is ROHS3 compliant with MSL Level 1 (unlimited moisture sensitivity). The LF412MH/NOPB carries ECCN EAR99 classification. Both parts are HTSUS 8542.33.0001 classified. Verify specific compliance requirements for your application before final selection.