LM285BXM-1.2 Equivalent & Substitute Parts

Part Overview

The LM285BXM-1.2 is a Shunt Voltage Reference IC manufactured by Texas Instruments, designed for precision voltage reference applications requiring a fixed 1.235V output. This Surface Mount device operates across the industrial temperature range of -40°C to 85°C and delivers 20 mA output current with ±1% tolerance.

The LM285BXM-1.2 is currently designated as Last Time Buy, indicating that Texas Instruments has discontinued or will discontinue production. Identifying equivalent substitute parts is essential for design continuity, long-term supply chain planning, and ensuring component availability for new production runs and field replacements.

Substiute Parts

LM285BXM-1.2

Texas InstrumentsIn Stock: 3716LM285BXM-1.2 Datasheet

Current PartRFQ

LM285BXM-1.2/NOPB

National SemiconductorIn Stock: 1545LM285BXM-1.2/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM285BXM-1.2 is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Reference Type: Shunt
• Output Type: Fixed
• Voltage - Output (Fixed): 1.235V
• Current - Output: 20 mA
• Tolerance: ±1%
• Temperature Coefficient: 30 ppm/°C
• Noise - 10Hz to 10kHz: 60 µVrms
• Current - Cathode: 10 µA
• Operating Temperature Range: -40°C to 85°C
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• RoHS Status: ROHS3 Compliant

The LM285BXM-1.2/NOPB qualifies as a parametric equivalent substitute because it matches all mandatory electrical and mechanical specifications. Both devices are functionally interchangeable in applications requiring a fixed 1.235V shunt voltage reference with identical performance characteristics and package form factor.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: LM285BXM-1.2/NOPB

The LM285BXM-1.2/NOPB (National Semiconductor) is a direct parametric equivalent to the LM285BXM-1.2. All electrical specifications, mechanical dimensions, and environmental compliance certifications are identical. The substitute part is currently in Active product status, ensuring ongoing availability and supply chain stability.

Compliance Considerations:

Both the main part and substitute are ROHS3 Compliant, meeting environmental regulatory requirements for lead-free manufacturing and hazardous substance restrictions. The MSL rating of 1 (Unlimited) for the primary part indicates minimal moisture sensitivity; this characteristic supports reliable handling and storage without specialized desiccant packaging requirements.

Supply Chain Advantage:

Given the Last Time Buy status of the LM285BXM-1.2, transitioning to the LM285BXM-1.2/NOPB provides access to active inventory (1495 Pcs reported in stock) and ensures long-term component availability for production and field service applications.

Frequently Asked Questions (FAQ)

Q1: Can the LM285BXM-1.2/NOPB be used as a direct replacement for the LM285BXM-1.2?

A: Yes. The LM285BXM-1.2/NOPB is a parametric equivalent substitute. All electrical characteristics (1.235V fixed output, 20 mA current, ±1% tolerance, 30 ppm/°C temperature coefficient, 60 µVrms noise), operating temperature range (-40°C to 85°C), and package form factor (8-SOIC) are identical. No circuit modifications or PCB redesign are required.

Q2: What does the "/NOPB" suffix indicate?

A: The "/NOPB" suffix denotes "No Plumbum" (lead-free) packaging and manufacturing process. This designation confirms compliance with RoHS directives and indicates the part is manufactured without lead-based solder or finishes.

Q3: Are there any differences in packaging or handling between these parts?

A: Both parts use identical 8-SOIC Surface Mount packaging with 0.154" (3.90mm) width. The MSL rating of 1 (Unlimited) for the primary part indicates minimal moisture sensitivity. Handling and storage procedures are equivalent for both devices.

Q4: Why is the LM285BXM-1.2 designated as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has announced end-of-life for this product. Customers are advised to place final orders before production discontinuation. The LM285BXM-1.2/NOPB, with Active product status, provides continuity for ongoing applications.

Q5: What are the critical parameters that must match for substitution?

A: Substitution requires exact matching of: Reference Type (Shunt), Output Type (Fixed), Output Voltage (1.235V), Output Current (20 mA), Tolerance (±1%), Temperature Coefficient (30 ppm/°C), Noise specification (60 µVrms at 10Hz to 10kHz), Cathode Current (10 µA), Operating Temperature Range (-40°C to 85°C), and Package Type (8-SOIC). Any deviation in these parameters disqualifies a part as a direct substitute.

Q6: Is PCB layout modification necessary when switching to the substitute part?

A: No. Both parts share identical pinout, package dimensions, and electrical characteristics. Existing PCB layouts designed for the LM285BXM-1.2 are fully compatible with the LM285BXM-1.2/NOPB without modification.