Monolithic Power Systems Inc. EVQ3369-R-01A

Overview

EVQ3369-R-01A from Monolithic Power Systems is an evaluation board for the MPQ3369 6-channel boost white LED driver IC, supporting up to 100mA per channel, 15000:1 PWM dimming ratio, and I²C programmable control. It implements peak-current-mode PWM regulation with six independent cathode current sinks, 2.5% inter-string current matching, and operates from 3.5V–36V input for mid- to small-size LCD backlighting.

For engineers reviewing the EVQ3369-R-01A datasheet, EVQ3369-R-01A pinout, EVQ3369-R-01A application, or EVQ3369-R-01A equivalent, this board enables rapid validation of MPQ3369's multi-dimming modes (analog/PWM/mix), phase-shift noise reduction, thermal current derating, and fault reporting via I²C register access and hardware signals (EN, PWM, FAULT).

Technical Context

The EVQ3369-R-01A implements a complete reference design for the MPQ3369GR QFN-24 WLED driver, integrating all required passive components-including 22µH power inductor, 4.7µF/50V output capacitors, 100Ω current-sense resistors per string, and Schottky diodes-configured for 6-string operation at ≤50V LED output and 12V nominal input.

It supports three dimming architectures: direct PWM input (100Hz–20kHz), analog dimming via DC voltage on ADJ pin, and mixed-mode dimming with configurable transfer points (25%/12.5%), all selectable via I²C registers or MIX/AD pin logic. Phase shift between channel PWMs is implemented to reduce EMI peaks during high-ratio dimming.

Key Specifications

Availability

EVQ3369-R-01A is available at Aetrix Electronics and suitable for LCD backlight development, automotive display prototyping, and portable device lighting validation requiring stable component supply, traceable evaluation hardware, and full register-level debug capability.

Supply support for EVQ3369-R-01A 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 power management ICs, with expertise in DC/DC converters, LED drivers, motor drivers, and battery management solutions.

The MPQ3369 product line targets high-efficiency, high-dimming-ratio backlighting for compact displays, emphasizing low EMI, thermal robustness, and flexible digital/analog control-enabling thin, energy-efficient LCD panels in tablets, notebooks, and automotive infotainment systems.

FAQ

What input voltage range does the EVQ3369-R-01A support?

The board accepts 3.5V to 36V DC between VIN and GND terminals, matching the MPQ3369's operational input range. This allows testing under automotive battery conditions (e.g., cold-crank 6V, load-dump 36V) and standard 12V/24V industrial supplies without external regulators.

How are the six LED strings connected to the evaluation board?

Each string connects between the common LED+ terminal and one of six dedicated cathode outputs: LED1 through LED6. These pins route directly to the MPQ3369's internal current sinks; no external current-setting resistors are needed as R_SET values are pre-populated on-board for 50mA per string calibration.

Can the switching frequency be adjusted, and how?

Yes-f_SW is programmable from 200kHz to 2.2MHz using either an external resistor on RT pin, I²C register writes (REG 0x02), or synchronization to an external clock signal applied to SYNC pin. Default configuration uses a 191kΩ resistor for ~1MHz operation.

Does the board support thermal derating of LED current?

Yes-the MPQ3369 automatically reduces per-string current above 125°C junction temperature, and this behavior is fully active on the EVQ3369-R-01A. The FAULT pin asserts and I²C status register bit OTP_FLAG goes high when thermal shutdown is triggered.

Is external I²C hardware required to configure the MPQ3369?

No-while the EVKT-USBI2C-02 kit is recommended for GUI-based register access, basic functionality (EN, PWM dimming) works standalone. SCL/SDA pins are broken out to 0.1" headers, enabling connection to any I²C master (e.g., Arduino, Raspberry Pi, or custom MCU) using standard pull-up resistors.

What protections are demonstrated on this board?

All MPQ3369-integrated protections are implemented and testable: over-current (cycle-by-cycle limiting), over-voltage (programmable LED OVP threshold), over-temperature (junction sensing), LED open/short detection, and inductor short protection. Fault conditions drive the FAULT pin low and set corresponding bits in I²C status registers.