Texas Instruments LM2588T-3.3/NOPB

Overview

LM2588T-3.3/NOPB from Texas Instruments is a monolithic 5-A flyback/boost regulator IC with fixed 3.3-V output, NPN internal switch rated for 65-V standoff and 5-A peak current, 4–40-V input range, and adjustable 100–200-kHz switching frequency - used in isolated DC-DC power supplies for industrial control and telecom infrastructure.

For engineers reviewing the LM2588T-3.3/NOPB datasheet, LM2588T-3.3/NOPB pinout, LM2588T-3.3/NOPB application, or LM2588T-3.3/NOPB equivalent, key selection criteria include output voltage tolerance (±4% over line/load), shutdown quiescent current (<60 μA), current-mode control for transient response, thermal/UVLO protection, and TO-220-7 package thermal performance.

Technical Context

The LM2588T-3.3/NOPB integrates a current-mode PWM controller, 5-A NPN power switch, error amplifier with 1.23-V reference, soft-start circuit, and synchronization input. Its architecture supports flyback, forward, and boost topologies via external transformer or inductor selection.

It operates with internal current limiting (5.0–9.5 A), undervoltage lockout (3.05–3.75 V), and thermal shutdown (150°C max junction). Frequency is set by an external resistor on Pin 1 or synchronized externally via Pin 6, enabling multi-rail noise coordination.

Key Specifications

Pinout & Package

LM2588T-3.3/NOPB uses the NDZ (TO-220-7) package: 10.1 mm × 8.89 mm body, vertical mounting, bent staggered leads, with exposed tab electrically connected to Pin 2 (Ground).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar flyback/boost regulator applications.

Compared with LM2587T-3.3/NOPB, the LM2588T-3.3/NOPB delivers 67% higher switch current and adds synchronization for EMI control; versus UC3845N, it reduces component count by integrating switch and fixed reference but trades off flexibility and peak efficiency.

Availability

LM2588T-3.3/NOPB is available at Aetrix Electronics and suitable for industrial PLC power supplies, telecom line card biasing, and automotive body control modules requiring stable component supply and long-lifecycle support.

Supply support for LM2588T-3.3/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 headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The LM2588 series was designed specifically for cost-sensitive, medium-power isolated and non-isolated DC-DC conversion - targeting flyback, forward, and boost topologies where integration, reliability, and ease of use supersede ultra-high efficiency.

FAQ

What is the maximum output power achievable with LM2588T-3.3/NOPB in a flyback configuration?

The LM2588T-3.3/NOPB supports up to ~20 W in well-designed flyback configurations using its 5-A/65-V NPN switch, standard TI-recommended transformers, and proper thermal management on a TO-220-7 package with ≥4 in² copper area. Output power is limited by switch conduction losses, transformer coupling, and thermal dissipation - not by the IC alone. Real-world designs typically deliver 15–18 W continuous at 3.3 V with >85% efficiency. LM2588T-3.3/NOPB datasheet Figure 54 shows a validated 12-V flyback example; scaling to 3.3 V requires adjusting turns ratio and output rectifier.

Does LM2588T-3.3/NOPB require external feedback resistors?

No, LM2588T-3.3/NOPB does not require external feedback resistors. It integrates a trimmed internal voltage reference and fixed 3.3-V feedback network - Pin 3 (Feedback) connects directly to the output node through a small RC filter for stability. This eliminates resistor tolerance errors and temperature drift affecting output accuracy. The LM2588T-3.3/NOPB datasheet Section 7.2 confirms R1/R2 are omitted for fixed-output versions, unlike the adjustable LM2588 variant. Using external dividers would disrupt regulation and void the ±4% system tolerance guarantee.

How is thermal performance managed in the TO-220-7 package of LM2588T-3.3/NOPB?

LM2588T-3.3/NOPB's NDZ (TO-220-7) package achieves θ_JA = 45°C/W with 4 in² of 1-oz copper, per datasheet Section 6.8. Effective thermal management requires mounting the exposed tab (Pin 2/GND) to a large copper pour using thermal vias and optionally an external heatsink. Junction temperature must stay below 150°C - derating curves in Figure 1 show supply current vs. temperature. For continuous 1.75-A output, board layout must minimize trace resistance and ensure airflow. LM2588T-3.3/NOPB includes thermal shutdown, but sustained operation near limit degrades reliability.

Can LM2588T-3.3/NOPB be synchronized to an external clock, and what are the timing requirements?

Yes, LM2588T-3.3/NOPB supports external synchronization via Pin 6 (Sync). A negative-going pulse with <100 ns rise/fall time and amplitude ≥0.4 V (min) and ≤1.0 V (max) at 200 kHz triggers alignment - datasheet Figure 21 specifies V_STH = 0.625–0.875 V and I_SYNC = 100–200 μA. The switch turns on within 700 ns of the sync pulse falling edge. This allows precise multi-rail coordination in telecom or test equipment. LM2588T-3.3/NOPB must be configured for same nominal frequency as master source; mismatch causes jitter or loss of lock.

What protection features are built into LM2588T-3.3/NOPB?

LM2588T-3.3/NOPB integrates three core protections: (1) Current limiting (5.0–9.5 A) via internal sense and comparator, (2) Undervoltage lockout (3.05–3.75 V) preventing operation during brownout, and (3) Thermal shutdown at 150°C junction temperature. All are fully internal - no external components needed. Additionally, the IC draws <60 μA in shutdown (Pin 1 ≥3 V), and soft-start prevents inrush. These features protect both LM2588T-3.3/NOPB and downstream circuitry during fault conditions like shorted outputs or overheating.