Monolithic Power Systems Inc. MP4034GS

Overview

MP4034GS from Monolithic Power Systems is a primary-side-controlled offline LED driver IC with integrated 700V MOSFET, delivering precise constant-current regulation up to 7W in flyback DCM operation. It eliminates opto-coupler and secondary feedback components, supports universal AC input (85–265VAC), and features natural EMI spectrum shaping for reduced filter cost. Used in isolated/non-isolated LED lighting systems requiring high reliability and low BOM count.

For engineers reviewing the MP4034GS datasheet, MP4034GS pinout, MP4034GS application, or MP4034GS equivalent, key selection criteria include its 700V drain rating, VCC UVLO thresholds (6.3V/17.3V), FB OVP dual-level protection (4.0V/6.35V), DCM detection at 120mV, and SOIC8-7A thermal performance (θJA = 76°C/W).

Technical Context

The MP4034GS implements primary-side regulation via auxiliary winding sampling to reconstruct secondary current without isolation components. Its variable off-time control enforces discontinuous conduction mode (DCM) by detecting zero-current crossing through FB voltage decay (≥120mV drop), ensuring stable constant-current output across line and load variations.

It integrates a 700V vertical DMOS power switch with 13Ω typical R_DS(on), a 550µA high-voltage startup current source, and dual-level over-voltage protection triggered at FB = 4.0V (constant-voltage foldback) and 6.35V (immediate shutdown). Thermal shutdown activates at 150°C with 30°C hysteresis.

Key Specifications

Pinout & Package

MP4034GS is housed in a standard SOIC8-7A package (JEDEC MS-012), featuring exposed thermal pad on underside for enhanced heat dissipation. Pin 1 is marked with notch or dot; pin numbering follows standard SOIC convention (counterclockwise from top-left corner).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar offline LED driver applications.

Compared with MP4034GS, MP4024GS sacrifices universal-input capability and safety margin for lower cost, while BP57728 increases design complexity and EMI filtering requirements despite similar output power-making MP4034GS optimal for new universal-input LED driver designs demanding reliability and regulatory simplicity.

Availability

MP4034GS is available at Aetrix Electronics and suitable for LED street lighting, commercial downlights, industrial indicator modules, and smart home bulb drivers requiring stable component supply, long-lifecycle support, and RoHS-compliant manufacturing.

Supply support for MP4034GS 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 analog semiconductor company specializing in high-performance power management ICs, founded in 1997 and headquartered in Kirkland, WA.

The MP4034GS belongs to MPS's offline LED driver product line, engineered specifically for cost-sensitive, high-reliability AC/DC LED lighting applications where primary-side regulation, integrated HV MOSFETs, and EMI optimization are critical.

FAQ

What is the maximum recommended output power for MP4034GS?

The MP4034GS is rated for up to 7W output power under typical conditions (TA = 25°C, SOIC8-7A on 4-layer PCB with adequate copper pour). At higher ambient temperatures or with limited PCB thermal relief, derating is required-e.g., ≤5W at 70°C ambient-to maintain junction temperature below 125°C and ensure long-term reliability.

Does MP4034GS require an external startup resistor?

No. The MP4034GS integrates a 550µA high-voltage current source referenced to the Drain pin, enabling direct startup from rectified AC without external resistor. This internal source automatically disables once VCC reaches 17.3V, improving efficiency during normal operation.

How does MP4034GS detect open-circuit LED faults?

MP4034GS monitors the FB pin for a −0.15V falling edge during each switching cycle. If this edge is absent-indicating no secondary current flow and thus an open LED string-the IC immediately halts switching and enters hiccup mode, discharging VCC until UVLO restarts the cycle after fault removal.

Can MP4034GS operate in continuous conduction mode (CCM)?

No. MP4034GS is designed exclusively for discontinuous conduction mode (DCM) operation. Its DCM detection circuit samples FB voltage decay; if the 120mV falling edge is not detected within the expected time window, the IC stops switching to prevent CCM entry and maintain regulation accuracy.

What is the purpose of the four GND pins on MP4034GS?

The four GND pins (pins 2, 4, 5, 6) provide low-impedance return paths for power, signal, and substrate currents. They minimize ground bounce during high dI/dt switching, improve noise immunity on the sensitive FB pin, and enhance thermal conduction from the die to PCB copper, supporting higher power density layouts.

Is MP4034GS compliant with IEC 61000-4-5 surge immunity standards?

MP4034GS itself is not certified to IEC 61000-4-5, but its 700V drain rating and integrated OVP enable robust system-level surge protection when paired with appropriate MOVs, X/Y capacitors, and RCD snubbers. Reference design MP4034-LED-EV1 achieves 4kV line-earth surge immunity per IEC 61000-4-5 Level 3.

What is the minimum recommended FB resistor divider value?

MPS recommends FB resistor divider values between 10kΩ and 100kΩ total resistance to limit noise coupling. A series 1kΩ–2kΩ resistor between FB and the divider improves noise rejection and suppresses substrate injection effects-critical for stable regulation in noisy EMI environments.