Monolithic Power Systems Inc. MP4032-1GS

Overview

MP4032-1GS from Monolithic Power Systems is a TRIAC-dimmable, primary-side-controlled offline LED driver IC with an integrated 500V/1A MOSFET in SOIC8-7A package. It delivers ≤6W output power, achieves >0.9 power factor via boundary-conduction-mode PFC, and enables flicker-free dimming across 74–76% phase range using real-current control without secondary feedback. It targets compact, cost-sensitive residential LED lamps.

For engineers reviewing the MP4032-1GS datasheet, MP4032-1GS pinout, MP4032-1GS application, or MP4032-1GS equivalent, key selection criteria include its integrated 500V MOSFET, VCC UVLO (13.8V turn-on / 9.4V resume), COMP OCP threshold (5.0V), ZCD-based zero-current detection (0.35V threshold), and SOIC8-7A thermal resistance (θJA = 96°C/W).

Technical Context

The MP4032-1GS implements proprietary real-current control by correlating primary-side CS-sensed current with MULT-derived line-voltage reference to regulate secondary LED current without optocoupler or secondary shunt. Its multiplier output (0–3V) shapes the current envelope sinusoidally for high PF.

It operates in boundary-conduction mode with programmable minimum off-time (5.6μs) and leading-edge blanking (310ns on CS), while ZCD pin provides valley-switching trigger (0.35V falling edge) and over-voltage protection sampling (5.3V threshold after 1.9μs blanking).

Key Specifications

Pinout & Package

MP4032-1GS is housed in an SOIC8-7A package (8-pin, 7.6mm × 4.9mm, 1.27mm pitch) with exposed pad for thermal enhancement. Pin 7 is NC; all other pins are functional and validated per MPS datasheet Rev. 1.02.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side-controlled LED driver applications.

Compared with MP4032-1GS, MP4032-1GZ offers identical performance in tape-and-reel format for SMT lines, while BP5758D trades integration for higher power scalability but adds design complexity and reduces dimming fidelity.

Availability

MP4032-1GS is available at Aetrix Electronics and suitable for residential LED bulbs, commercial downlights, and industrial panel lights requiring stable component supply, long-lifecycle support, and RoHS-compliant sourcing.

Supply support for MP4032-1GS 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with design centers in the US, China, and Taiwan.

The MP4032 product line targets cost-sensitive, TRIAC-dimmable LED lighting applications requiring single-stage PFC, integrated HV MOSFETs, and flicker-free dimming-optimized for A19, GU10, and PAR30 lamp designs.

FAQ

What is the maximum recommended output power for MP4032-1GS?

The MP4032-1GS is rated for ≤6W output power per the datasheet's typical application and thermal limits. This is constrained by its 1.3W continuous power dissipation (SOIC8-7A, θJA = 96°C/W) and 1A drain current rating. Exceeding 6W risks thermal shutdown or reduced lifetime under sustained load.

How does the MP4032-1GS achieve power factor correction without a secondary feedback loop?

It uses primary-side real-current control: the MULT pin senses rectified line voltage to generate a sinusoidal reference, while the CS pin measures primary current. The internal multiplier compares these to shape the primary current envelope, achieving >0.9 PF without optocoupler or secondary sensing components.

Can MP4032-1GS drive more than 6 LEDs in series?

Yes, provided the total forward voltage stays within the flyback transformer's secondary output capability and the ZCD-based OVP threshold (calculated as VOUT_OVP = 5.3V × NSEC/NAUX) remains above the maximum expected output voltage. Design must verify minimum off-time and boundary-mode stability at full load.

What is the purpose of the DRAIN pin beyond MOSFET switching?

The DRAIN pin supplies charging current to the VCC capacitor during start-up via an internal high-voltage charger, enabling fast turn-on (<130µs startup timer) without external bias winding. Once operational, the auxiliary winding takes over VCC supply, and the DRAIN charger disables.

Does MP4032-1GS support trailing-edge (ELV) dimmers?

No-the MP4032-1GS is specifically designed for leading-edge TRIAC dimmers. Its MULT pin dimming detection and proprietary algorithm are optimized for phase-cut waveforms with abrupt turn-on edges; ELV dimmer compatibility is not specified or guaranteed.

How is over-voltage protection implemented without direct output sensing?

OVP uses the ZCD pin to monitor the auxiliary winding voltage, which scales linearly with output voltage (VOUT ∝ NAUX/NSEC × VZCD). When ZCD exceeds 5.3V after 1.9µs blanking, the IC latches off until VCC drops to 7.5V, enabling safe restart without secondary-side components.

What layout practices are critical for stable MP4032-1GS operation?

Key practices include: (1) short, low-inductance CS and ZCD traces with local ceramic bypass caps; (2) separation of power and analog GND with single-point tie at IC GND; (3) ≥6mm creepage between primary and secondary sides; and (4) direct routing of DRAIN and CS to transformer/ground to minimize ringing and false triggering.