Monolithic Power Systems Inc. EV4688-N-00A

Overview

EV4688-N-00A from Monolithic Power Systems is an evaluation board for the MP4688DN buck white LED driver IC, designed to drive single-string high-power LEDs up to 19 LEDs (≈32V forward voltage) with regulated 730mA current, supporting 4.5–80V input and automotive/industrial lighting applications.

For engineers reviewing the EV4688-N-00A datasheet, EV4688-N-00A pinout, EV4688-N-00A application, or EV4688-N-00A equivalent, this board enables rapid validation of MP4688DN's hysteretic control, 2MHz switching, PWM dimming up to 20kHz, short-circuit protection, and thermal shutdown in real-world LED string configurations.

Technical Context

The EV4688-N-00A implements the MP4688DN - a monolithic synchronous buck LED driver with integrated high-side MOSFET, 200mV current-sense reference, and no-output-capacitor architecture. It operates in constant-current mode with ±5% ILED accuracy and supports analog/PWM dimming via dedicated EN/DIM pins.

Board-level design includes a 47µH power inductor (HC8LP-470-R), dual 2.2µF/100V ceramic input capacitors (GRM32ER72A225K), and Schottky rectifier D1 (STPS1H100U). The 0.56Ω sense resistors R1/R2 set nominal 730mA LED current per the 200mV reference.

Key Specifications

Availability

EV4688-N-00A is available at Aetrix Electronics and suitable for automotive headlight prototypes, industrial high-bay LED drivers, and general-purpose constant-current LED test platforms requiring stable component supply and fast design iteration.

Supply support for EV4688-N-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, motor drivers, and battery management.

The MP4688DN product line targets high-reliability, high-efficiency LED lighting systems where wide-input operation, integrated protection, and minimal external components are critical - especially in automotive front-lighting and industrial retrofit applications.

FAQ

What is the maximum LED string voltage supported by EV4688-N-00A?

The board supports up to 19 LEDs in series, assuming ~3.2V average forward voltage per LED, resulting in ≈61V total string voltage. With 80V max input and typical 1.5V dropout, it safely drives strings up to ~78V under worst-case conditions, verified using the HC8LP-470-R inductor and STPS1H100U rectifier.

How is LED current set on this evaluation board?

LED current is set by two parallel 0.56Ω sense resistors (R1 and R2), yielding 0.28Ω total resistance. With the MP4688DN's 200mV current-sense reference, this establishes 714mA nominal current (200mV / 0.28Ω), aligned with the documented 730mA typical value within tolerance and PCB trace resistance effects.

Can EV4688-N-00A operate without PWM dimming?

Yes - the DIM pin can be tied to EN via a 0Ω resistor (R3 location), enabling analog dimming through EN voltage modulation or simple on/off control. The board includes footprint R3 for this configuration, and the MP4688DN supports both PWM and analog dimming modes independently.

Does EV4688-N-00A include overvoltage protection?

No - the MP4688DN does not integrate output overvoltage protection. The board relies on input overvoltage handling (up to 80V) and LED open-circuit detection via current-sense monitoring. External OVP circuitry must be added if required for system-level safety compliance.

What thermal performance can be expected during continuous operation?

Under 60V input and 730mA load driving 10 LEDs (~32V), the MP4688DN in SOIC8-EP package reaches ≤85°C case temperature with standard 2-layer FR4 and 2oz copper, validated by thermal imaging in MPS Rev. 1.1 documentation. Thermal shutdown activates at 150°C junction temperature.

Is the board RoHS-compliant and halogen-free?

Yes - all bill-of-materials components listed in the schematic (including GRM32ER72A225K, STPS1H100U, HC8LP-470-R, and MP4688DN) are RoHS 2015/863/EU compliant and halogen-free per MPS documentation and manufacturer declarations.