LM385BM Equivalent & Substitute Parts

Part Overview

The LM385BM is a shunt voltage reference IC manufactured by Texas Instruments, classified as a Power Management (PMIC) component. This adjustable shunt voltage reference operates with a minimum output voltage of 1.24V and maximum of 5.3V, delivering up to 20mA output current with ±1% tolerance. The LM385BM is currently listed as obsolete, making identification of equivalent and substitute parts essential for ongoing design support and component procurement.

Substiute Parts

LM385BM

Texas InstrumentsIn Stock: 1547LM385BM Datasheet

Current PartRFQ

LM385BM-1.2/NOPB

Texas InstrumentsIn Stock: 3926LM385BM-1.2/NOPB Datasheet

DirectRFQ

LM385BM/NOPB

Texas InstrumentsIn Stock: 1763LM385BM/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM385BM is determined by strict alignment of the following electrical and mechanical parameters:

Critical Substitution Parameters:

• Reference Type: Shunt
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Mounting Type: Surface Mount
• Tolerance: ±1%
• Temperature Coefficient: 150ppm/°C
• Operating Temperature Range: 0°C ~ 70°C (TA)

Output Configuration Consideration: The LM385BM features an adjustable output voltage range (1.24V to 5.3V). Substitute parts may be available in either adjustable or fixed output configurations. Fixed output variants (such as LM385BM-1.2/NOPB with 1.235V fixed output) are functionally equivalent when the application requires operation within their specified fixed voltage range.

Identified Substitute Parts:

• LM385BM/NOPB: Direct functional equivalent with identical electrical specifications and active product status
• LM385BM-1.2/NOPB: Fixed output variant suitable for applications requiring 1.235V reference voltage

Parameter Comparison

Engineering Selection Recommendations

LM385BM/NOPB is the primary substitute for the obsolete LM385BM. This part maintains identical electrical specifications including adjustable output voltage range (1.24V to 5.3V), output current (20mA), tolerance (±1%), and thermal characteristics. The LM385BM/NOPB carries active product status and ROHS3 compliance, providing long-term availability and regulatory alignment for new designs and production continuity.

LM385BM-1.2/NOPB serves as an alternative for applications requiring a fixed 1.235V reference voltage output. This fixed-output variant differs from the main part in output configuration and exhibits lower cathode current (15µA versus 55µA) and slightly elevated noise floor (60µVrms versus 50µVrms). Selection of this part is appropriate only when the application design specifies operation at the 1.235V fixed reference point. This part also carries active product status and ROHS3 compliance.

Frequently Asked Questions (FAQ)

Q: Can LM385BM/NOPB directly replace LM385BM in existing designs? A: Yes. LM385BM/NOPB is electrically and mechanically identical to LM385BM, with the same 8-SOIC package, adjustable output voltage range, and electrical performance specifications. The primary difference is product status: LM385BM/NOPB is active while LM385BM is obsolete.

Q: When should LM385BM-1.2/NOPB be used instead of LM385BM/NOPB? A: LM385BM-1.2/NOPB should be selected only when the application circuit is designed for a fixed 1.235V reference voltage output. This part is not suitable for applications requiring the adjustable voltage range of 1.24V to 5.3V provided by the LM385BM or LM385BM/NOPB.

Q: Are there package compatibility differences between these parts? A: No. All three parts (LM385BM, LM385BM/NOPB, and LM385BM-1.2/NOPB) use the 8-SOIC surface mount package with identical 0.154" (3.90mm) width. PCB footprints and soldering processes are interchangeable.

Q: What is the impact of the noise specification difference between LM385BM/NOPB and LM385BM-1.2/NOPB? A: LM385BM-1.2/NOPB exhibits 60µVrms noise (10Hz to 10kHz) compared to 50µVrms for LM385BM/NOPB. This 10µVrms difference is relevant only in precision analog applications with stringent noise requirements. For general reference voltage applications, this difference is typically negligible.

Q: Does the lower cathode current of LM385BM-1.2/NOPB (15µA versus 55µA) affect circuit design? A: The cathode current specification indicates the minimum operating current required for proper device operation. The lower cathode current of LM385BM-1.2/NOPB may reduce power consumption in some circuit topologies but does not affect voltage reference accuracy or output current capability. Circuit design must ensure minimum cathode current requirements are met for the selected part.

Q: Are all three parts RoHS compliant? A: LM385BM is RoHS non-compliant. Both LM385BM/NOPB and LM385BM-1.2/NOPB are ROHS3 compliant, meeting current regulatory requirements for new designs and production.