Texas Instruments LM3404HVMA

Overview

LM3404HVMA from Texas Instruments is a monolithic 1-A constant-current buck regulator IC designed for high-power LED driving, featuring integrated high-side N-channel MOSFET (R_DS(on) = 0.75 Ω typ), 6–75 V input range, 200 mV current-sense threshold, hysteretic controlled-on-time architecture, and thermal shutdown at 165°C. It delivers stable current to series/parallel LED arrays in automotive headlamps and industrial lighting systems.

For engineers reviewing the LM3404HVMA datasheet, LM3404HVMA pinout, LM3404HVMA application, or LM3404HVMA equivalent, key selection considerations include VIN range compatibility (up to 75 V), PWM dimming support via DIM pin, RON-programmable on-time, open-LED protection using CS overvoltage comparator (300 mV), and SO PowerPAD™-8 thermal performance (R_θJB = 24.5°C/W).

Technical Context

The LM3404HVMA implements a controlled-on-time (COT) architecture combining hysteretic valley-current regulation with an external RON-set one-shot timer - eliminating need for loop compensation. Its CS pin compares sensed voltage across RSNS against a precise 200 mV reference to initiate switching, while the 300 ns minimum off-time enforces duty-cycle limits for output voltage control.

It integrates a 7-V internal linear regulator (VCC) with UVLO (5.3 V), bypassed by ≥0.1 µF ceramic capacitor, and uses bootstrap gate drive (BOOT–SW) with external 10-nF CB capacitor to sustain high-side MOSFET operation. Thermal shutdown (165°C, 25°C hysteresis) and cycle-by-cycle current limiting (1.5 A typ) provide robust fault protection.

Key Specifications

Pinout & Package

LM3404HVMA is housed in an 8-pin SO PowerPAD™ package (3.90 mm × 4.89 mm) with exposed thermal pad (DAP) requiring 4–6 vias to PCB ground plane for optimal thermal dissipation (R_θJB = 24.5°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with LM3404MA, LM3404HVMA adds 33 V headroom for 48 V industrial and load-dump tolerant designs; versus MPQ4425HGQ-A, it trades synchronous efficiency for simplicity and HV robustness - making LM3404HVMA optimal for cost-sensitive, thermally demanding, wide-input LED drivers.

Availability

LM3404HVMA is available at Aetrix Electronics and suitable for automotive lighting, industrial machine vision systems, and outdoor street lighting requiring stable component supply across extended temperature and voltage ranges.

Supply support for LM3404HVMA 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, embedded processing, and power management technologies, with leadership in high-reliability industrial and automotive ICs.

The LM3404HVMA belongs to TI's LED driver product line, engineered specifically for robust, high-efficiency constant-current regulation in harsh-environment lighting applications - emphasizing thermal resilience, wide-input operation, and system-level fault protection.

FAQ

What is the maximum input voltage supported by the LM3404HVMA?

The LM3404HVMA supports a maximum input voltage of 75 V, as specified in its absolute maximum ratings and recommended operating conditions. This 75 V rating distinguishes it from the standard LM3404 (42 V max) and enables use in 48 V industrial systems, commercial vehicle electrical architectures, and applications subject to load-dump transients. Operation above 75 V risks permanent damage, and the device enters undervoltage lockout below 6 V.

How does the LM3404HVMA achieve constant LED current without external compensation components?

The LM3404HVMA uses a controlled-on-time (COT) hysteretic architecture that compares the CS pin voltage against a 200 mV internal reference to determine switch activation. Because regulation relies on valley-current sensing and fixed on-time (set by RON), no error amplifier or external compensation network is needed - simplifying layout, improving transient response, and ensuring stability across all output capacitor types including zero-capacitor configurations.

Can the LM3404HVMA drive LED strings without an output capacitor?

Yes, the LM3404HVMA supports capacitor-less LED driving due to its current-mode topology and inherent inductor current control. The device regulates average LED current directly via the CS feedback loop, eliminating dependency on output voltage stabilization. A small 10 nF capacitor across the LED array is recommended to dampen high-frequency ringing at the SW node, but bulk output capacitance is optional and not required for basic regulation.

What thermal performance can be expected from the LM3404HVMA in a typical PCB layout?

In a standard 4-layer PCB with 4–6 thermal vias connecting the SO PowerPAD™ DAP to an internal ground plane, the LM3404HVMA achieves a junction-to-board thermal resistance (R_θJB) of 24.5°C/W. At 1.2 A output and 24 V input, typical power dissipation is ~0.9 W; this yields ~22°C temperature rise above board temperature - enabling reliable operation at 125°C junction limit even in convection-cooled enclosures.

Does the LM3404HVMA provide protection against open-circuit LED failure?

Yes, the LM3404HVMA includes built-in open-LED protection via its CS pin overvoltage comparator, which trips at 300 mV. During an open-circuit event, CS voltage collapses toward 0 V, causing the controller to command maximum duty cycle - but the OVP comparator immediately disables the switch once VSNS exceeds 300 mV, clamping output voltage and preventing destructive overvoltage at the LED terminals.