Monolithic Power Systems Inc. MPQ3367GRE-AEC1-P

Overview

MPQ3367GRE-AEC1-P from Monolithic Power Systems is a 6-channel, AEC-Q100 qualified boost WLED driver with peak-current-mode control, designed for automotive and industrial LCD backlighting. It delivers up to 150mA per channel, supports 15000:1 PWM dimming ratio at ≤200Hz, integrates a 100mΩ/50V internal MOSFET, and features I²C programmability, phase-shifted PWM dimming, and robust fault protection including LED short/open, OVP, OTP, and OCP.

For engineers reviewing the MPQ3367GRE-AEC1-P datasheet, MPQ3367GRE-AEC1-P pinout, MPQ3367GRE-AEC1-P application, or MPQ3367GRE-AEC1-P equivalent, key selection criteria include its 3.5–36V input range, 2.5% inter-channel current matching, QFN-24 4mm×4mm wettable flank package, AEC-Q100 Grade 1 qualification (−40°C to +125°C), and support for analog/PWM/mix dimming modes with programmable thresholds.

Technical Context

The MPQ3367 employs peak-current-mode PWM control with cycle-by-cycle current limiting and an internal 100mΩ low-side MOSFET switch operating up to 2.2MHz. Its six independent current sinks regulate LED string current via external ISET resistor (1.2V reference) with ±2.5% matching across channels and 350–1000mV headroom voltage depending on load.

Dimming is implemented through three configurable modes-direct PWM, analog (via 8-bit DAC), and mix dimming with 25%/12.5% transfer points-selected via I²C or MIX/AD pin voltage (0.3V/0.5–0.8V/1.0–1.3V). Phase shift (60° for 6 strings, 90° for 4) reduces EMI and audible noise during PWM dimming, while frequency spread spectrum further enhances EMI performance.

Key Specifications

Pinout & Package

MPQ3367GRE-AEC1-P is housed in a wettable flank QFN-24 package (4mm × 4mm, 0.5mm pitch), optimized for automated optical inspection (AOI) and solder joint reliability in automotive production. Exposed thermal pad is connected to AGND.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 6-channel boost WLED driver applications.

Compared with MPQ3367GRE-AEC1-P, the GR variant sacrifices AOI capability for lower unit cost, while the GF variant trades compactness for enhanced thermal handling-making the GRE the optimal balance of automotive compliance, manufacturability, and board space efficiency.

Availability

MPQ3367GRE-AEC1-P is available at Aetrix Electronics and suitable for automotive instrument clusters, center stack infotainment displays, industrial HMI panels, and commercial tablet backlighting requiring stable component supply, AEC-Q100 qualification, and long-term lifecycle support.

Supply support for MPQ3367GRE-AEC1-P 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 MPQ3367 belongs to MPS's automotive-grade LED driver product line, engineered specifically for high-reliability LCD backlighting in vehicles-emphasizing AEC-Q100 compliance, wide input range, ultra-deep dimming, and integrated fault diagnostics.

FAQ

What is the maximum allowable LED string voltage supported by MPQ3367GRE-AEC1-P?

The device regulates output voltage based on the highest forward voltage among active LED strings, with absolute maximum ratings of +50V on LED1–LED6 pins. Practical string voltage is limited by the OVP threshold (programmable 1.9–2.1V on OVP pin), which sets the upper bound of the regulated output. For example, with a 12V input and 6-series-white-LED string (~18V VF), the boost converter delivers ~20V while maintaining OVP margin.

How does the phase-shift function improve EMI performance?

By staggering the turn-on timing of each LED channel's current sink-60° apart for 6 strings-the MPQ3367GRE-AEC1-P spreads switching energy across time, reducing peak inrush current and harmonic content. This lowers conducted and radiated EMI, especially in the 150–500MHz band critical for automotive EMC compliance, without requiring additional filtering components.

Can MPQ3367GRE-AEC1-P drive fewer than 6 LED strings?

Yes. Unused LED channels (e.g., LED6 for 5-string configuration) are disabled by connecting the corresponding LEDx pin to GND with a 270pF capacitor (≤470pF), enabling automatic detection during startup. Alternatively, the CH2:0 register bits (via I²C) can disable channels 2–6 individually, allowing flexible 1–6 string configurations without hardware changes.

What is the role of the STH pin, and how is it configured?

STH is a 18μA current source used to set the LED short-protection threshold voltage. Connecting a resistor from STH to GND programs the threshold (e.g., 100kΩ → 1.8V). If left floating, the internal TH_S1:0 register selects fixed thresholds (e.g., 5V for TH_S1:0 = 01). This allows precise tuning to avoid false trips during transient LED voltage drops.

Does MPQ3367GRE-AEC1-P support I²C clock stretching?

No. The MPQ3367GRE-AEC1-P implements a standard I²C slave interface compliant with SMBus 2.0 timing, supporting 400kHz clock rate, but does not perform clock stretching. All register reads/writes complete within one SCL period, ensuring deterministic communication for real-time dimming updates and fault status polling.

How is thermal derating implemented in this device?

MPQ3367GRE-AEC1-P includes optional thermal foldback: when junction temperature exceeds the OTP threshold (170°C, 20°C hysteresis), the internal circuitry automatically reduces LED current proportionally to maintain safe operation. This behavior is enabled via I²C register bit THERMAL_DEGRADE and prevents catastrophic failure during sustained high-temperature operation.

What is the minimum recommended ISET resistor value, and why?

The minimum recommended ISET resistor is 10kΩ, setting ~120mA/channel (based on ILED = 1.2V / RISET). Lower values increase current but risk exceeding the 150mA/channel absolute maximum and degrading current matching accuracy due to increased sense voltage error. At 10kΩ, the device operates within guaranteed ±2.5% matching and thermal limits.