Monolithic Power Systems Inc. EV4050A-J-00A

Overview

EV4050A-J-00A from Monolithic Power Systems is an evaluation board for the MP4050AGJ constant-current LED driver IC, implementing a high-side buck topology to deliver 40V/115mA output from universal AC input (85–265VAC, 50/60Hz), with integrated 500V MOSFET, >85% efficiency, and compliance with EN55015 conducted EMI and IEC61000-4-5 ±1kV surge immunity.

For engineers reviewing the EV4050A-J-00A datasheet, EV4050A-J-00A pinout, EV4050A-J-00A application, or EV4050A-J-00A equivalent, this board enables rapid validation of non-isolated AC/DC LED driver designs targeting GU10 lamps, industrial lighting, and cost-sensitive general illumination systems requiring low component count and thermal foldback protection.

Technical Context

The EV4050A-J-00A implements a primary-side regulated, off-line, non-isolated buck converter using the MP4050AGJ IC in TSOT23-5 package. It operates in discontinuous conduction mode (DCM) with internal 200ns leading-edge blanking and maximum frequency limiting to suppress audible noise.

Protection features include VCC under-voltage lockout (UVLO) with hysteresis, open LED protection (OLP), short-circuit protection (SCP), over-temperature protection (OTP) with auto-restart, and integrated thermal current foldback - all implemented without external sensing components beyond R3/R4 current-sense resistors.

Key Specifications

Availability

EV4050A-J-00A is available at Aetrix Electronics and suitable for LED bulb replacement, industrial lighting control, and general illumination development requiring stable component supply, fast prototyping turnaround, and pre-validated EMI/surge performance.

Supply support for EV4050A-J-00A 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 core expertise in DC/DC conversion, LED drivers, and motor control solutions.

The MP4050A product line targets cost-sensitive, space-constrained off-line LED lighting applications - delivering integrated high-voltage switching, precision current regulation, and robust protection in minimal footprint.

FAQ

What is the recommended input fuse rating for EV4050A-J-00A?

The board includes FR1, a 10Ω/1W fusible resistor rated for inrush current limiting and overcurrent protection. For agency-compliant end equipment, a certified 1A slow-blow fuse (e.g., Littelfuse 0455001.MR) is recommended in series with the L terminal, per IEC61347-1 requirements.

Can EV4050A-J-00A drive multiple LED strings in parallel?

No - the board is configured for single-string constant-current operation only. Parallel strings require individual current regulation to prevent thermal runaway; the MP4050AGJ does not support multi-string sensing or balancing, and the EVB layout lacks provisions for additional sense paths or isolation.

Is isolation required when operating EV4050A-J-00A on bench power?

Yes - the board is non-isolated and connects directly to AC mains. All testing must use an isolation transformer on the input side, as explicitly stated in the safety warning. Direct connection to utility power without isolation violates lab safety standards and risks electric shock.

What is the role of R5 (10kΩ) across L1?

R5 damps resonance in the π-filter formed by C2, L1, and C3. Its 10kΩ value provides optimal damping without significantly loading the filter or degrading EMI performance - confirmed by measured conducted emissions data meeting EN55015 limits.

Does EV4050A-J-00A support dimming functionality?

No - the board implements fixed-frequency, fixed-output-current operation with no provision for TRIAC, PWM, or analog dimming interface. The MP4050AGJ IC lacks dedicated dimming pins or adjustable frequency modulation; dimming requires external circuitry not included on this evaluation board.

What is the thermal shutdown threshold of MP4050AGJ on this board?

The MP4050AGJ IC triggers over-temperature protection at 150°C junction temperature, with hysteresis of 20°C (restart at ~130°C). On EV4050A-J-00A, thermal performance is enhanced by copper pour on the bottom layer and placement of C1/C4 near heat sources, enabling continuous operation at 25°C ambient with full load.