Monolithic Power Systems Inc. MP3376GR-XXXX-Z

Overview

MP3376GR-XXXX-Z from Monolithic Power Systems is an 8-channel synchronous boost WLED driver with I²C interface, designed for LCD backlighting in tablets and notebooks. It delivers up to 50mA per channel with ±2.5% current matching, supports input voltages from 3V to 30V, regulates output up to 36V, and integrates dual MOSFETs (160mΩ LS / 260mΩ HS) for high-efficiency LED current sourcing.

For engineers reviewing the MP3376GR-XXXX-Z datasheet, MP3376GR-XXXX-Z pinout, MP3376GR-XXXX-Z application, or MP3376GR-XXXX-Z equivalent, key selection criteria include I²C-configurable dimming modes (analog/mixed), programmable switching frequency (350kHz–2.4MHz), thermal/overvoltage/short-string protection thresholds, and QFN-24 package compatibility with PCB layout constraints for multi-string backlight systems.

Technical Context

The MP3376 employs peak-current-mode control with a fixed 10MHz internal clock to achieve precise PWM dimming resolution and stable boost regulation across varying LED forward voltages. Its feedback loop automatically selects the lowest active LEDX voltage as reference, enabling dynamic output voltage adjustment to power all strings without overvoltage stress.

It implements four dimming modes-two analog (via PWM pin or I²C) and two mixed (with 6.25%/12.5%/25%/50% transfer points)-and supports linear fade-in/fade-out via programmable current slope (2–128µs/step). Protection includes cycle-by-cycle current limiting (1.8A/2.5A), LED short detection (2.5/5/7.5/10V thresholds), and latch-off fault handling for inductor/diode shorts.

Key Specifications

Pinout & Package

MP3376GR-XXXX-Z is housed in a thermally enhanced QFN-24 (4mm × 4mm) package with exposed pad (EP) tied to PGND for optimal heat dissipation in compact backlight modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with RT8542GQW and ISL97693IRZ, MP3376GR-XXXX-Z provides higher per-channel current (50mA vs. 40mA), integrated synchronous rectification (reducing conduction loss and BOM), and full I²C configurability-including OTP-programmable defaults and mixed-dimming transfer points-making it optimal for next-generation portable and automotive displays demanding precision, density, and reliability.

Availability

MP3376GR-XXXX-Z is available at Aetrix Electronics and suitable for tablet backlight systems, notebook display modules, automotive infotainment units, and industrial HMI panels requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP3376GR-XXXX-Z 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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MP3376 belongs to MPS's WLED backlight driver product line, engineered specifically for energy-efficient, high-precision LCD panel illumination in space-constrained portable and automotive displays.

FAQ

What is the function of the FT pin on MP3376GR-XXXX-Z?

The FT (Fault Terminal) pin is an open-drain output that pulls low during normal operation to enable an external PMOS transistor for input disconnection. When a fault occurs (e.g., LED short or OVP), FT floats high, turning off the PMOS and isolating the input supply. This provides hardware-level fault containment without MCU intervention.

How does MP3376GR-XXXX-Z handle unused LED channels during startup?

During startup, MP3376GR-XXXX-Z automatically detects unused LED strings by monitoring LEDX pin voltage levels. If an LEDX pin is tied to GND or its corresponding CHEN bit is cleared via I²C, the channel is excluded from the feedback loop and current regulation, preventing false OVP trips and ensuring stable output for remaining active strings.

Can MP3376GR-XXXX-Z operate without an external bootstrap capacitor?

No. The BST pin requires a 100nF ceramic capacitor connected in series with a 47Ω resistor to the SW node to properly bias the high-side MOSFET gate. Omitting this network disables synchronous rectification, degrades efficiency, and risks unstable switching or device latch-up under load.

What is the minimum recommended PWM dimming frequency for achieving 100:1 dimming ratio?

A 22kHz PWM dimming frequency is specified to achieve ≥100:1 dimming ratio in mixed-dimming mode with 25% transfer point. Lower frequencies extend the ratio further but increase audible noise risk; higher frequencies reduce ratio depth due to limited minimum on-time (≥1.5µs required for stable LED current turn-on).

Does MP3376GR-XXXX-Z support I²C write-protection after OTP programming?

Yes. After OTP programming of registers 00H–04H, the OTPEN bit (02H-D10) resets to 0 and cannot be re-enabled. Registers 03H and 04H are one-time programmable; registers 00H–02H allow up to five OTP writes. Subsequent I²C writes to protected bits are ignored, ensuring firmware-immutable default settings.

How is LED short protection threshold configured on MP3376GR-XXXX-Z?

The LED short protection threshold is set via LEDS1:0 bits (Register 03H[7:6]) to select 2.5V, 5V, 7.5V, or 10V. Detection triggers after 1.5–2ms of sustained overvoltage, marking the faulty string and disabling it while allowing remaining strings to continue regulation - critical for maintaining partial backlight functionality in multi-string arrays.

What thermal resistance values apply to the QFN-24 package of MP3376GR-XXXX-Z?

The MP3376GR-XXXX-Z QFN-24 (4mm × 4mm) package has θ_JA = 46°C/W and θ_JC = 10°C/W when mounted on a 4-layer JEDEC-standard PCB (JESD51-7). These values assume proper thermal via placement under the exposed pad (EP) connected to a solid PGND plane for effective heat extraction.