Monolithic Power Systems Inc. MP3376AGR-XXXX-Z

Overview

MP3376AGR-XXXX-Z from Monolithic Power Systems is an 8-channel synchronous boost WLED driver IC for LCD backlighting in tablets and notebooks, featuring I²C programmability, 3–30V input range, up to 37.5V output, and ±2.5% LED current matching across channels.

For engineers reviewing the MP3376AGR-XXXX-Z datasheet, MP3376AGR-XXXX-Z pinout, MP3376AGR-XXXX-Z application, or MP3376AGR-XXXX-Z equivalent, key selection criteria include I²C-addressable dimming modes (analog/mixed), selectable switching frequencies up to 2.4MHz, integrated 4.9V LDO, and fault protection including LED short/open, OVP, OTP, and cycle-by-cycle current limiting.

Technical Context

The MP3376A employs peak-current-mode control with a fixed 10MHz internal clock to achieve high-resolution dimming and stable boost regulation. Its synchronous rectifier uses integrated HS-FET (260mΩ) and LS-FET (160mΩ) to minimize conduction loss and eliminate external diode requirements.

Eight independent current sources are regulated via feedback from the lowest active LEDX voltage, enabling automatic output voltage optimization across mixed-string configurations. Protection logic includes programmable LED short thresholds (2.5/5/7.5/10V), OVP (24/31/37.5V), and latch-off current limit triggered at 3.5A within 200ns over five cycles.

Key Specifications

Pinout & Package

MP3376AGR-XXXX-Z is housed in a thermally enhanced QFN-24 (4mm × 4mm) package with exposed pad (EP) for GND connection, supporting high-power LED driving with low thermal resistance (θ_JA = 46°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with RTQ2132B-QA and ISL97693IRZ-T7A, MP3376AGR-XXXX-Z offers broader switching frequency selection (up to 2.4MHz), integrated 4.9V LDO, and unique mixed-dimming architecture-enabling deeper dimming ratios and simplified system-level power sequencing.

Availability

MP3376AGR-XXXX-Z is available at Aetrix Electronics and suitable for tablet backlighting, notebook display systems, automotive infotainment panels, and industrial HMIs requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP3376AGR-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, Korea, and Taiwan.

The MP3376A belongs to MPS's WLED backlight driver product line, engineered specifically for energy-efficient, high-brightness LCD panel illumination in space-constrained portable and automotive displays.

FAQ

What is the function of the FT pin on MP3376AGR-XXXX-Z?

The FT (Fault Terminal) pin serves as an open-drain output that pulls low to enable an external PMOS transistor for input power disconnection during fault conditions. When no disconnection is needed, FT is left floating and the inductor connects directly to VIN. It supports fault isolation without requiring additional control logic.

How does the MP3376A handle unused LED channels during startup?

The MP3376A automatically detects unused LED strings by monitoring LEDX pin voltages at startup. If an LEDX pin is tied to GND or its corresponding CHEN bit is set to 0, the channel is excluded from regulation and protection monitoring-preventing false OVP trips and ensuring stable output for remaining active strings.

Can MP3376AGR-XXXX-Z operate without an external bootstrap capacitor?

No. The BST pin requires a 100nF ceramic capacitor and 47Ω resistor in series connected to SW to properly bias the internal high-side MOSFET gate. Omitting this network disables synchronous rectification, degrades efficiency, and may cause erratic switching or thermal overstress under load.

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

A 22kHz PWM dimming frequency (set via FPWM3:0 = 1010b) is required to achieve ≥100:1 dimming ratio in mixed dimming mode. Lower frequencies increase audible noise; higher frequencies reduce achievable depth due to minimum on-time constraints (≥1.5µs recommended).

Does MP3376AGR-XXXX-Z support daisy-chained I²C configuration?

Yes - using A0 and A1 pins, up to four MP3376A devices can share one I²C bus with unique addresses (0x28–0x2B). This enables multi-zone backlight control without address conflicts or additional GPIO resources from the host controller.

What protection features are activated during LED short conditions?

During LED short events, the MP3376A monitors LEDX pin voltage against programmable thresholds (2.5/5/7.5/10V). If exceeded for 1.8ms (at 1.2MHz f_SW), the affected channel is marked off and disabled. All channels shorted triggers full converter shutdown until VIN or EN is cycled.

Is the internal 4.9V LDO (VCC) powered when VIN is below 6V?

No - the internal LDO only activates when VIN exceeds 6V. Below that, VCC drops to 0V and the IC remains disabled until VIN rises above the 2.5V UVLO threshold and VCC stabilizes. External 4.9V bias is not supported; operation below 6V requires disabling the LDO-dependent functions or using alternate biasing.