Texas Instruments LM2586S-5.0/NOPB

Overview

LM2586S-5.0/NOPB from Texas Instruments is a monolithic 3-A step-up (boost) and flyback switching regulator IC with fixed 5.0 V output, 4 V to 40 V input range, NPN 65 V switch, and current-mode control. It delivers ±4% system output voltage tolerance over line and load, supports external frequency adjustment up to 200 kHz, and integrates soft-start, shutdown, and thermal/UVLO protection - used in industrial power supplies requiring isolated or boosted DC rails.

For engineers reviewing the LM2586S-5.0/NOPB datasheet, LM2586S-5.0/NOPB pinout, LM2586S-5.0/NOPB application, or LM2586S-5.0/NOPB equivalent, key selection criteria include its fixed 5 V output configuration, TO-263-7 (DDPAK) package thermal performance, 3 A switch current capability, flyback/boost topology flexibility, and compatibility with standard inductor families for rapid design implementation.

Technical Context

The LM2586S-5.0/NOPB implements current-mode control using an internal error amplifier (1.23 V reference), transconductance of 0.75 mmho, and voltage gain of 165 V/V, enabling precise regulation under dynamic load and line transients. Its oscillator supports programmable frequency (100–200 kHz via external resistor) and synchronization via pin 6, allowing multi-device coordination without beat-frequency noise.

It features a dedicated ON/OFF pin (pin 1) with 1.6 V threshold and 40 μA input current, enabling low-power shutdown drawing ≤60 μA total supply current. Protection includes cycle-by-cycle current limiting, thermal shutdown, and undervoltage lockout at 3.3 V nominal, ensuring robust operation across −40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

LM2586S-5.0/NOPB is packaged in a 7-pin DDPAK/TO-263 (KTW) thermally enhanced surface-mount package (14.986 mm × 10.16 mm), designed for high-power dissipation with PCB copper area as heatsink.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-up/flyback regulator applications.

Compared with LM2586S-5.0/NOPB, LM2587S-5.0/NOPB offers higher current headroom in identical packaging, while TPS40210DGQ provides architectural flexibility at the cost of integration - both require revalidation of compensation, magnetics, and thermal layout.

Availability

LM2586S-5.0/NOPB is available at Aetrix Electronics and suitable for industrial sensor power supplies, automotive body control modules, telecom remote feeders, and PLC I/O cards requiring stable component supply and long-term manufacturability.

Supply support for LM2586S-5.0/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company specializing in analog and embedded processing technologies, with leadership in power management ICs for industrial, automotive, and communications markets.

The LM2586 product line delivers monolithic flyback/boost regulators optimized for cost-sensitive, high-reliability power conversion - designed to simplify isolated and non-isolated DC-DC design with minimal external components.

FAQ

What is the maximum input voltage rating for LM2586S-5.0/NOPB?

The LM2586S-5.0/NOPB has an absolute maximum input voltage rating of 45 V, with recommended operating range from 4 V to 40 V. This allows reliable operation in automotive cold-crank (down to 4 V) and load-dump (up to 40 V) conditions. Exceeding 45 V risks permanent damage to the internal NPN switch and control circuitry - always include input clamping or TVS protection if transient voltages may exceed this limit.

Does LM2586S-5.0/NOPB require external feedback resistors to set the output voltage?

No, LM2586S-5.0/NOPB does not require external feedback resistors. It is a fixed 5.0 V output variant with internal resistor divider connected to the feedback pin, delivering ±4% system output voltage tolerance over line, load, and temperature. External resistors are only needed for the adjustable version (LM2586SX-ADJ/NOPB) - using them on LM2586S-5.0/NOPB would disrupt regulation and is not supported.

Can LM2586S-5.0/NOPB be used in flyback topology with transformer isolation?

Yes, LM2586S-5.0/NOPB is explicitly designed for flyback regulator applications, as confirmed in its product description and typical application circuits. Its NPN switch, current-mode control, and internal 1.23 V reference enable stable isolated output generation. When configured as flyback, it supports multiple outputs, galvanic isolation, and output voltages both above and below the input range - all without modifying the IC itself.

What thermal considerations apply to LM2586S-5.0/NOPB in TO-263 package?

LM2586S-5.0/NOPB in the KTW (TO-263-7) package has a junction-to-ambient thermal resistance of 56°C/W with minimal copper and 26°C/W with 1.0064 in² of 1 oz. copper - meaning PCB copper area is critical for thermal performance. For 3 A continuous operation, ≥0.4896 in² of thermal pad is recommended. Thermal shutdown activates at 150°C junction temperature, so thermal vias and heatsinking must be verified per actual load and ambient conditions.

Is LM2586S-5.0/NOPB pin-compatible with other members of the LM2586 family?

Yes, LM2586S-5.0/NOPB shares identical pinout and package (TO-263-7) with LM2586S-3.3/NOPB, LM2586S-12/NOPB, and LM2586SX-ADJ/NOPB - enabling direct substitution in existing layouts when changing output voltage requirements. All variants use the same functional pin assignments (e.g., pin 3 = Feedback, pin 7 = Switch), though feedback network design differs for adjustable versions.