Monolithic Power Systems Inc. MP4033GSE-Z

Overview

MP4033GSE-Z from Monolithic Power Systems is a TRIAC-dimmable, primary-side-control offline LED controller with integrated active PFC, designed for isolated flyback LED drivers up to 50W. It delivers accurate LED current regulation using real-current control, operates in boundary-conduction mode (BCM), and supports analog dimming via PWM input and warm sunset color-temperature control via the DIM pin.

For engineers reviewing the MP4033GSE-Z datasheet, MP4033GSE-Z pinout, MP4033GSE-Z application, or MP4033GSE-Z equivalent, key selection considerations include its adaptive leading/trailing-edge dimmer detection, programmable NTC-based thermal fold-back, ZCD-based zero-current switching, internal 30V/250mΩ MOSFET, and SOIC-14 package compatibility with high-voltage AC line interfacing.

Technical Context

The MP4033GSE-Z implements proprietary real-current control that derives LED current accuracy from primary-side sensing-eliminating optocoupler and secondary-side feedback. Its multiplier circuit (MULT pin) shapes the current reference to match rectified line voltage phase, enabling >0.95 power factor without external PFC controllers.

It uses adaptive dimmer-type detection based on MULT pin waveform analysis and timing thresholds (tLEADING = 86–134 µs, tTRAILING = 388–602 µs), then applies phase-cut-based dimming control with dedicated pull-down current sources (IDP_TL = 133–167 mA) and clamped COMP output (VCOMPL_TL = 1.53–1.64 V) to ensure deep dimming down to <5% and flicker-free operation across legacy TRIAC dimmers.

Key Specifications

Pinout & Package

MP4033GSE-Z is packaged in SOIC-14 with exposed pad (RoHS-compliant, lead-free). The package provides thermal performance of θJA = 86 °C/W and θJC = 38 °C/W on a 4-layer PCB, supporting continuous operation up to 50W in thermally constrained designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar TRIAC-dimmable offline LED controller applications.

Compared with MP4032GSE-Z, MP4033GSE-Z adds integrated MOSFET and DAMP driver for simplified 50W designs; versus BP5778E, it delivers active PFC, adaptive dimmer detection, and programmable thermal fold-back-making it the only choice for high-PF, warm-dimming, thermally robust residential/commercial LED drivers.

Availability

MP4033GSE-Z is available at Aetrix Electronics and suitable for residential indoor lighting, commercial office lighting, and industrial high-bay lighting requiring stable component supply, long-lifecycle support, and RoHS-compliant manufacturing.

Supply support for MP4033GSE-Z 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, and global distribution through authorized partners.

The MP4033 belongs to MPS's LED lighting controller product line, engineered specifically for TRIAC-dimmable, single-stage isolated AC/DC LED drivers requiring high power factor, deep dimming, and thermal resilience in compact form factors.

FAQ

What dimmer types does MP4033GSE-Z support?

MP4033GSE-Z automatically detects and supports both leading-edge (TRIAC) and trailing-edge (ELV) dimmers using MULT pin waveform analysis and time thresholds (tLEADING = 86–134 µs, tTRAILING = 388–602 µs). It achieves deep dimming down to 5% with minimal flicker and no manual configuration.

How does the real-current control method eliminate the need for an optocoupler?

The real-current control method calculates LED current from primary-side parameters: VREF (0.414 V), transformer turns ratio (N), and sense resistor (Rs), using I_LED ≈ (VREF × N) / (2 × Rs). This eliminates secondary-side feedback components while maintaining ±3% current accuracy across line, load, and temperature.

Can MP4033GSE-Z be used without the internal MOSFET?

No-the internal 30V/250mΩ MOSFET is integral to the control architecture and VCC charging circuit (D pin supplies current to VCC via internal JFET/diode). External high-side switching requires MP4032GSE-Z, which lacks the integrated MOSFET and DAMP pin.

What is the role of the DAMP pin, and how is it used?

The DAMP pin drives an external damping MOSFET to suppress voltage ringing during TRIAC dimmer commutation. It reduces EMI, prevents false zero-crossing detection, and improves dimmer compatibility-especially with low-power or aging dimmers that exhibit high dv/dt transients.

How does NTC-based thermal fold-back extend LED lifetime?

By connecting an NTC thermistor to the NTC pin, the MP4033GSE-Z reduces LED current when ambient temperature exceeds VH_NTC (1.14–1.36 V), typically corresponding to >60°C. This lowers junction temperature, slowing lumen depreciation and preventing thermal runaway-extending usable life by up to 2× in enclosed fixtures.

Is MP4033GSE-Z compatible with non-isolated buck-derived topologies?

No-it is designed exclusively for isolated flyback topologies with auxiliary winding feedback. The ZCD pin requires reflected voltage from an auxiliary winding to enable zero-current switching; non-isolated topologies lack this signal path and cannot meet the device's timing and protection requirements.

What protection features activate during output short-circuit conditions?

During LED short-circuit, MP4033GSE-Z reduces switching frequency to 7 kHz, limiting output power to a safe level. Simultaneously, ZCD-based OVP remains active, and if VZCD exceeds 4.90–5.70 V, the gate driver shuts off. All protections feature auto-restart after VCC drops below 6.55–7.45 V (VCCEN).