TL2843BD Equivalent & Substitute Parts

Part Overview

The TL2843BD is a boost, flyback, and forward regulator controller IC manufactured by Texas Instruments, designed for positive output step-up and step-up/step-down DC-DC conversion applications. This 14-SOIC surface mount device operates across a 7.6V to 30V supply voltage range with switching frequencies up to 500kHz and a maximum duty cycle of 96%. The part is currently in Last Time Buy status, making identification of functionally equivalent alternatives essential for design continuity and long-term supply chain planning.

Substiute Parts

TL2843BD

Texas InstrumentsIn Stock: 2121TL2843BD Datasheet

Current PartRFQ

TL2843BDR

Texas InstrumentsIn Stock: 19801TL2843BDR Datasheet

MFR RecommendedRFQ

UC2843BDG

onsemiIn Stock: 3434UC2843BDG Datasheet

MFR RecommendedRFQ

UC2843BDR2G

onsemiIn Stock: 4015UC2843BDR2G Datasheet

MFR RecommendedRFQ

UC3843BVDR2G

onsemiIn Stock: 2487UC3843BVDR2G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TL2843BD is determined by strict alignment across the following critical parameters:

• Package / Case: 14-SOIC (0.154", 3.90mm Width) — ensures mechanical and electrical compatibility with existing PCB layouts
• Output Type: Transistor Driver — maintains functional equivalence in gate drive capability
• Function: Step-Up, Step-Up/Step-Down — confirms topology support
• Voltage - Supply (Vcc/Vdd): 7.6V ~ 30V — establishes input voltage compatibility
• Frequency - Switching: Up to 500kHz — ensures timing and performance alignment
• Duty Cycle (Max): 96% — confirms operational envelope compatibility
• Number of Outputs: 1 — maintains single-output configuration
• Mounting Type: Surface Mount — preserves assembly compatibility
• RoHS Status: ROHS3 Compliant — ensures regulatory compliance

The following parts meet these substitution criteria and are therefore considered equivalent alternatives to the TL2843BD.

Parameter Comparison

Engineering Selection Recommendations

TL2843BDR (Texas Instruments) — Recommended as the primary substitute. This part maintains identical electrical specifications and operating temperature range to the TL2843BD while offering Active product status, ensuring continued availability and manufacturing support. Both parts are manufactured by Texas Instruments and carry ROHS3 compliance.

UC2843BDR2G (onsemi) — Suitable alternative with Active product status and Tape & Reel packaging. Operates within the same supply voltage and switching frequency parameters. Operating temperature range is -25°C to 85°C, which is narrower than the TL2843BD. This part is appropriate for applications not requiring the full -40°C lower temperature specification.

UC3843BVDR2G (onsemi) — Viable substitute with Active product status and extended operating temperature range of -40°C to 105°C, exceeding the TL2843BD specification. Suitable for applications requiring enhanced thermal performance or operation in elevated temperature environments. Cut Tape & Digi-Reel packaging is available.

UC2843BDG (onsemi) — Not recommended for new designs. Although electrically compatible, this part carries Obsolete product status, limiting long-term supply availability and manufacturing support.

Frequently Asked Questions (FAQ)

Q: Can I use TL2843BDR as a direct replacement for TL2843BD?

A: Yes. The TL2843BDR is a direct functional equivalent with identical electrical specifications, package type (14-SOIC), and operating temperature range (-40°C to 85°C). The primary difference is product status: TL2843BDR is Active, while TL2843BD is Last Time Buy.

Q: What is the difference between UC2843BDR2G and UC3843BVDR2G?

A: Both are onsemi-manufactured alternatives with identical electrical performance and 14-SOIC packaging. The key difference is operating temperature range: UC2843BDR2G operates from -25°C to 85°C, while UC3843BVDR2G extends to -40°C to 105°C. Select UC3843BVDR2G for applications requiring the full -40°C lower temperature specification or operation above 85°C.

Q: Why is UC2843BDG listed as a substitute if it is Obsolete?

A: UC2843BDG meets all electrical and mechanical substitution criteria but carries Obsolete product status. It is included for reference in existing designs but is not recommended for new applications due to limited supply availability and lack of manufacturing support.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts carry ROHS3 Compliant status, matching the TL2843BD compliance profile.

Q: Does packaging type affect substitution eligibility?

A: All substitute parts use 14-SOIC surface mount packaging, ensuring mechanical compatibility with existing PCB layouts. Packaging variants (Tube, Tape & Reel, Cut Tape) do not affect electrical substitution but may influence procurement and assembly processes.

Q: Can I use these substitutes in forward converter topologies?

A: The TL2843BD and TL2843BDR explicitly support Boost, Flyback, and Forward topologies. The onsemi alternatives (UC2843 and UC3843 series) support Boost and Flyback topologies. Forward topology support is not specified for onsemi parts; application-specific validation is required if forward conversion is the intended topology.