Monolithic Power Systems Inc. MPQ3369GR-Z

Overview

MPQ3369GR-Z from Monolithic Power Systems is a 6-channel boost white LED driver IC designed for LCD backlighting in tablets and notebooks. It delivers up to 100mA per channel with 2.5% current matching, supports I²C configuration, and achieves a 15,000:1 PWM dimming ratio at ≤200Hz. Its integrated 100mΩ/50V MOSFET, peak-current-mode control, and phase-shift PWM dimming enable high-efficiency, low-noise operation in space-constrained displays.

For engineers reviewing the MPQ3369GR-Z datasheet, MPQ3369GR-Z pinout, MPQ3369GR-Z application, or MPQ3369GR-Z equivalent, key selection criteria include its 3.5–36V input range, QFN-24 (4mm×4mm) thermal performance, multi-dimming mode flexibility (PWM/analog/mix), configurable OVP/STH thresholds, and robust fault protection including LED open/short, OCP, OTP, and inductor short detection.

Technical Context

The MPQ3369GR-Z implements peak-current-mode PWM control for the boost converter, using an internal 100mΩ low-side MOSFET and adaptive output voltage regulation based on the lowest active LEDx pin voltage. Its six independent cathode-connected current sinks are trimmed to ±2.5% matching across channels at 20mA and 100mA loads.

Dimming is managed via three modes: direct PWM (LED current amplitude fixed, duty-following), analog (current scaled linearly with PWM duty), and mix dimming (25% or 12.5% transfer point between analog and PWM). Phase shift-60° for six channels, 90° for four-is applied to stagger LED current pulses and suppress audible noise and inrush currents during PWM dimming.

Key Specifications

Pinout & Package

MPQ3369GR-Z is housed in a thermally enhanced QFN-24 package (4mm × 4mm, 0.5mm pitch) with exposed thermal pad connected to AGND. The package supports high-power dissipation (θ_JA = 42°C/W) and requires controlled-impedance PCB layout for stable boost operation and EMI compliance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with RTQ2133BGQW and ISL97693IRTZ, MPQ3369GR-Z uniquely combines six-channel capability, 15,000:1 PWM dimming, hardware-configurable mix dimming, and integrated phase-shift timing-making it optimal for premium portable and automotive displays requiring both luminance precision and acoustic silence.

Availability

MPQ3369GR-Z is available at Aetrix Electronics and suitable for tablet backlighting, notebook display systems, and automotive infotainment panels requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MPQ3369GR-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 power management ICs, with expertise in DC/DC conversion, LED drivers, and motor control solutions.

The MPQ3369 belongs to MPS's high-dynamic-range WLED driver product line, engineered specifically for LCD backlight applications demanding ultra-deep dimming, multi-channel synchronization, and robust fault resilience in compact form factors.

FAQ

What dimming modes does MPQ3369GR-Z support, and how are they selected?

The MPQ3369GR-Z supports direct PWM, analog, and mix dimming modes. Selection is achieved either via the MIX/AD pin voltage (0.3V, 0.5–0.8V, or 1.0–1.3V) or through I²C register writes (MODE1:0 bits). Mix dimming uses a 25% or 12.5% transfer point to combine analog scaling at high brightness with PWM switching at low brightness, enabling smooth transitions and eliminating flicker.

How does the phase-shift function reduce audible noise in PWM dimming?

The phase-shift function staggers the turn-on timing of LED current sinks-by 60° for six active channels or 90° for four-distributing inrush current across the PWM period. This lowers peak input current harmonics and prevents mechanical vibration in inductors and capacitors, effectively eliminating coil whine commonly heard below 20kHz in portable displays.

Can MPQ3369GR-Z drive fewer than six LED strings, and how is channel disable handled?

Yes. Unused LEDx pins (e.g., LED6 for five-string operation) can be tied to AGND to auto-disable that channel at startup. Alternatively, the CH2:0 register bits configure active channel count (000 = all six, 101 = LED1 only). Auto-detection avoids current leakage and ensures accurate output voltage regulation based only on active strings.

What protections are implemented, and how are faults reported?

MPQ3369GR-Z integrates over-current (OCP), over-voltage (OVP), over-temperature (OTP), LED open/short, inductor short, and VOUT-to-GND short protection. All faults assert the open-drain FF pin low. OVP and STH thresholds are resistor-programmable; OTP is fixed at 170°C with 20°C hysteresis; fault latching requires EN toggle or I²C reset.

Is the internal MOSFET sufficient for typical 6-string WLED applications?

Yes. The integrated 100mΩ/50V N-channel MOSFET supports continuous 100mA per channel with typical boost efficiencies >88% at 12V input and 36V output. Its low R_DS(on) and optimized gate drive minimize conduction and switching losses, eliminating the need for external high-side switches in most medium-size display designs.

How is the 15,000:1 PWM dimming ratio achieved, and what limits apply?

This ratio is achieved by combining sub-7μs minimum on-time capability with deep-duty PWM control and output voltage clamping at 93% of OVP during ultra-short pulses. It is specified at f_PWM ≤ 200Hz; at higher frequencies (e.g., 20kHz), the practical ratio drops to ~200:1 due to timing resolution and settling constraints.

Does MPQ3369GR-Z require external compensation, and what topology is supported?

Yes. The COMP pin requires an external RC network (typically 1nF + 10kΩ in series) for loop stability in peak-current-mode control. The device supports standard boost topology with external inductor, diode, and output capacitor; it automatically regulates V_OUT to the minimum voltage required by the highest-voltage active LED string.