Texas Instruments LM3402HVMM

Overview

LM3402HVMM from Texas Instruments is a monolithic 0.5-A constant-current buck regulator with integrated 735-mA N-channel MOSFET, designed for driving high-power LED arrays in automotive and industrial lighting. It operates from 6 V to 75 V input, delivers precise 200-mV current-sense threshold regulation, supports PWM dimming via TTL-compatible DIM pin, and features hysteretic controlled-on-time (COT) architecture eliminating loop compensation.

For engineers reviewing the LM3402HVMM datasheet, LM3402HVMM pinout, LM3402HVMM application, or LM3402HVMM equivalent, key selection considerations include its 75-V max input rating, thermal shutdown at 165°C, 300-ns minimum off-time limiting VO(MAX), RON-programmable on-time, and support for ceramic-output or capacitor-less LED configurations.

Technical Context

The LM3402HVMM implements a controlled-on-time (COT) architecture combining hysteretic current-mode control with a voltage-inversely scaled one-shot timer. Its CS pin compares sensed voltage across RSNS against a 200-mV reference to initiate switching, while external RON sets tON per tON = 1.34×10⁻¹⁰ × RON/VIN.

It integrates a 7-V internal linear regulator (VCC) with UVLO at 5.25 V, bootstrap gate drive for high-side MOSFET with 10-nF CB requirement, and dual protection: cycle-by-cycle current limit at 735 mA (typ) and output overvoltage/overcurrent comparator tripping at 300 mV on CS.

Key Specifications

Pinout & Package

LM3402HVMM is housed in an 8-pin VSSOP (DGK) package with 3.00 mm × 3.00 mm body size and exposed thermal pad (DAP) requiring 4–6 vias to ground plane for thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3402MM and TPS92630QPWPRQ1, the LM3402HVMM uniquely combines 75-V operation, zero-compensation design, and capacitor-less capability-making it optimal for cost-sensitive, high-reliability industrial LED drivers where input voltage margin and simplicity are prioritized over automotive qualification or diagnostics.

Availability

LM3402HVMM is available at Aetrix Electronics and suitable for automotive lighting, industrial high-bay fixtures, and outdoor streetlight systems requiring stable component supply, long-term manufacturability, and robust transient handling.

Supply support for LM3402HVMM 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 delivering analog and embedded processing solutions, with leadership in power management ICs and high-reliability interface products.

The LM3402HVMM belongs to TI's LED driver product line, engineered specifically for efficient, compact, and robust constant-current regulation in high-power lighting applications across automotive, industrial, and infrastructure markets.

FAQ

What is the maximum input voltage supported by the LM3402HVMM?

The LM3402HVMM supports a maximum input voltage of 75 V, as specified in its absolute maximum ratings and recommended operating conditions. This 75-V rating enables direct use in 48-V industrial systems and automotive applications subject to load-dump transients. Operation above 75 V risks permanent damage; the device enters shutdown if VIN exceeds this limit during normal operation.

How does the LM3402HVMM achieve constant LED current without external compensation?

The LM3402HVMM uses a controlled-on-time (COT) hysteretic architecture that compares the CS pin voltage to a 200-mV internal reference. When current falls below regulation, the switch turns on for a VIN- and RON-determined duration, then shuts off for a fixed 300-ns minimum off-time. This self-stabilizing timing eliminates the need for external compensation components, simplifying design and improving transient response.

Can the LM3402HVMM operate without an output capacitor?

Yes, the LM3402HVMM supports capacitor-less LED operation due to its current-regulator topology and inherent inductor current control. The inductor directly sets LED ripple, and the CS comparator maintains regulation using only RSNS. A small 10-nF capacitor across the LED array is recommended to dampen ringing, but bulk output capacitance is optional and not required for stability.

What protection features are built into the LM3402HVMM?

The LM3402HVMM integrates thermal shutdown (165°C trip, 25°C hysteresis), cycle-by-cycle current limiting (735 mA typical), open-LED protection via CS overvoltage comparator (300 mV threshold), and input overvoltage clamping. It also includes VCC undervoltage lockout (5.25 V) and BOOT undervoltage lockout (1.7–4 V), ensuring safe startup and fault recovery without external supervision circuitry.

How is PWM dimming implemented on the LM3402HVMM?

PWM dimming on the LM3402HVMM is implemented through the DIM pin, which accepts TTL-level logic signals (VIH ≥ 2.2 V, VIL ≤ 0.8 V). A logic low disables the internal MOSFET, halting LED current flow while keeping VCC and bias circuits active for fast turn-on. The 75-µA internal pullup ensures default-on operation when DIM is left floating, eliminating the need for an external pullup resistor.