Monolithic Power Systems Inc. EV3399EY-00A

Overview

EV3399EY-00A from Monolithic Power Systems is an evaluation board for the MP3399EY 12-channel boost LED driver IC, configured with two parallel MP3399EY ICs to drive 24 independent white LED strings at up to 60mA per string, supporting 8–28V input and achieving ±2.5% inter-string current regulation for large LCD backlighting applications.

For engineers reviewing the EV3399EY-00A datasheet, EV3399EY-00A pinout, EV3399EY-00A application, or EV3399EY-00A equivalent, this board enables rapid validation of high-efficiency, multi-string LED backlight architectures with programmable OVP, PWM dimming, open/short LED protection, and thermal shutdown in notebook, monitor, and LCD TV designs.

Technical Context

The EV3399EY-00A implements a dual-MP3399EY architecture using external power MOSFETs (P-channel M1 and N-channel M2), fixed-frequency current-mode control, and per-string current ballast to maintain ≤2.5% current matching across 24 parallel LED strings. Each MP3399EY handles 12 strings with internal feedback sensing at low voltage (≤1.25V) to minimize conduction loss.

Protection features include under-voltage lockout (UVLO), cycle-by-cycle current limiting, over-voltage protection (OVP) with programmable threshold, open-LED and short-LED detection per channel, and thermal shutdown triggered at ≥150°C junction temperature - all implemented directly by the MP3399EY ICs on the board.

Key Specifications

Availability

EV3399EY-00A is available at Aetrix Electronics and suitable for LCD TV backlight validation, notebook PC display integration, and industrial monitor development requiring stable component supply and pre-validated reference design support.

Supply support for EV3399EY-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 MP3399EY product line targets large-panel LCD backlighting, delivering high-efficiency, multi-string current regulation with integrated protection for cost-sensitive, high-reliability display systems.

FAQ

What is the maximum total LED forward voltage supported by the EV3399EY-00A?

The board supports up to 12 series LEDs per string. With typical white LED V_F ≈ 3.2V, maximum string voltage is ~38.4V. The MP3399EY's internal OVP threshold is programmable up to 45V, allowing safe operation with margin for V_F variation and temperature drift.

Can the EV3399EY-00A be used with non-white LEDs?

Yes - the board drives any constant-current LED string within its voltage and current limits. Red, green, or blue LEDs may be substituted, but forward voltage differences require verification of boost converter headroom and adjustment of OVP threshold and current sense resistor values.

How is PWM dimming implemented on this board?

PWM dimming is applied via the DBRT pin, accepting 0–5V logic-level signals at 200Hz–2kHz. Internal circuitry modulates the MP3399EY's enable state synchronously with the PWM duty cycle, preserving current regulation accuracy and eliminating low-frequency flicker.

Does the board include thermal monitoring circuitry?

No discrete thermal sensor is present, but each MP3399EY IC integrates a thermal shutdown function triggered at ~150°C junction temperature. The board's copper pour and SOIC-28 package layout support adequate heat dissipation for evaluation-level continuous operation.

What external components must be changed to reduce max string current from 60mA to 30mA?

To scale current from 60mA to 30mA, replace R24 (0.05Ω, 1%, 1206) with a 0.1Ω, 1%, 1206 current sense resistor. All other biasing and feedback components remain unchanged, as the MP3399EY's internal reference and ballast circuitry retain full accuracy.

Is the EN pin active-high or active-low?

The EN pin is active-high: driving it to ≥2.0V (typically 5V) enables both MP3399EY ICs. Pulling EN low disables switching and places the drivers in ultra-low quiescent current mode (<100µA total).

Are schematics and layout files available for this evaluation board?

Yes - the official EV3399EY-00A Rev. 1.0 documentation (dated 9/23/2011) includes full schematic diagrams (pages 3–4), top/bottom PCB layer drawings (page 5), and BOM with manufacturer part numbers and footprints - all published on Monolithic Power Systems' website.