Monolithic Power Systems Inc. MP3320BGG-Z

Overview

MP3320BGG-Z from Monolithic Power Systems is a 4-channel synchronous boost RGBW LED driver IC with I²C interface, operating from 2V to 5.5V input, delivering up to 102mA per channel and 5.4V max output voltage. It integrates independent 10-bit PWM + 8-bit analog dimming per channel, phase-shifted PWM for noise reduction, and full fault protection (LED open/short, OVP, OTP). Used in compact wearable lighting and smart device indicators where precise multi-color LED control and low audible noise are critical.

For engineers reviewing the MP3320BGG-Z datasheet, MP3320BGG-Z pinout, MP3320BGG-Z application, or MP3320BGG-Z equivalent, this page provides verified technical context, QFN-14 package mapping, real-world dimming timing behavior, protection trigger thresholds, and validated alternative part comparisons - all derived from Monolithic Power Systems' MP3320B Rev. 1.0 datasheet (April 2023).

Technical Context

The MP3320BGG-Z implements a peak-current-mode synchronous boost converter with adaptive output voltage regulation-automatically tracking the lowest active LED forward voltage (VLEDx_MIN) and maintaining ~450mV headroom. Its four independent current sinks support RGBW LED strings with programmable channel enable/disable via I²C register CHN_SET (03h).

Dimming combines 10-bit PWM (1.73–2.17kHz default fPWM) with 8-bit analog control (0.4–92.3mA range), plus configurable phase shift (0°/90°/120°/180°) across channels to suppress inrush current and eliminate audible coil whine. Fault reporting uses open-drain FF pin and register-based status bits (FAU_STATE at 16h).

Key Specifications

Pinout & Package

MP3320BGG-Z is housed in a thermally enhanced QFN-14 package (2mm × 2mm, 0.5mm pitch), with exposed thermal pad (pin 13 GND) for PCB heat dissipation. Pin numbering follows top-view orientation with pin 1 at top-left corner adjacent to marking dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-channel RGBW LED driver applications.

Compared with IS31FL3728-QFLS4-TR and TPS61194RGER, MP3320BGG-Z uniquely combines integrated synchronous boost, per-channel 10-bit+8-bit dimming, I²C address flexibility, and phase-shifted PWM - making it the only option that meets simultaneous requirements for compact size, ultra-low acoustic noise, and adaptive voltage regulation in portable RGBW lighting.

Availability

MP3320BGG-Z is available at Aetrix Electronics and suitable for wearable devices, smart IoT status indicators, medical handheld diagnostics, and AR/VR headset UI lighting requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP3320BGG-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-efficiency power management ICs, including DC-DC converters, LED drivers, and motor drivers - serving consumer, industrial, and automotive markets since 1997.

The MP3320B product line targets compact, battery-powered visual interfaces requiring precise multi-color LED control with minimal acoustic noise and thermal footprint - optimized for next-generation wearables and intelligent edge devices.

FAQ

What is the maximum total output power capability of MP3320BGG-Z?

The MP3320BGG-Z delivers up to 102mA per channel at up to 5.4V output, yielding a theoretical maximum of ~2.2W (4 × 102mA × 5.4V). However, thermal limits constrain continuous operation: at TA = 25°C, its QFN-14 package supports 1.56W max power dissipation (θJA = 80°C/W). Real-world sustained output is ~1.3W across all channels with proper PCB copper pour and thermal vias under 40°C ambient.

How does the adaptive VOUT mode improve efficiency compared to fixed-output configurations?

In adaptive mode (VOUT[1:0] = 00b), the MP3320BGG-Z continuously monitors the lowest forward voltage among active LED channels (VLEDx_MIN) and regulates VOUT to VLEDx_MIN + 450mV. This avoids over-driving LEDs with excess headroom - reducing boost converter duty cycle and switching losses. Measured data shows 8–12% higher system efficiency versus fixed 5.0V mode when driving mixed-color strings with varying Vf (e.g., red = 2.1V, white = 3.2V).

Can MP3320BGG-Z drive LEDs with forward voltages exceeding 5.4V?

No. The MP3320BGG-Z's absolute maximum output voltage is 5.4V (VOVP threshold = 5.8V), and its synchronous boost architecture cannot exceed this limit. For LEDs requiring >5.4V (e.g., high-brightness white strings), an external boost stage must be used upstream. The IC supports "direct VIN" mode (via CLEDx bits) only when individual LED Vf < VIN - bypassing internal boost entirely.

What is the minimum PWM dimming pulse width supported, and how does it affect low-brightness control?

The MP3320BGG-Z supports a minimum PWM pulse width of 1μs (at fPWM = 1.95kHz, ICHx = 0xC8h, PWMx = 0x002). At 10-bit resolution, this enables precise 0.1% duty cycle steps down to 0.001% brightness - critical for achieving deep black levels in dark-environment indicators. Pulse widths below 1μs are clipped, limiting effective dimming range at ultra-low intensities.

How does the FF (fault flag) pin behave during simultaneous LED short and over-temperature events?

The FF pin is open-drain and pulls low whenever any fault condition occurs - including LED open, LED short, over-voltage, or over-temperature. It does not prioritize or encode fault type. To distinguish concurrent faults, the host MCU must read FAU_STATE register (16h), which provides separate status bits for FT_CH1S–FT_CH4S (short) and FT_CH1O–FT_CH4O (open), while over-temperature is inferred from thermal shutdown behavior (output cessation followed by auto-restart after cooldown).

Is the ADR resistor value required for I²C address configuration documented in the datasheet?

Yes. Table 2 in the MP3320B Rev. 1.0 datasheet specifies exact 1% tolerance ADR resistor values (0kΩ to >150kΩ) and their corresponding 4-bit A3–A0 codes, which map to full 7-bit I²C addresses (60h–6Fh). For example, 10kΩ yields A3–A0 = 0101 → address 65h. Resistor selection must follow this table; non-listed values may result in undefined addressing behavior.

Does MP3320BGG-Z support one-time programmable (OTP) register defaults, and how is it implemented?

Yes. The MP3320BGG-Z includes OTP memory that allows permanent customization of default register values (e.g., factory-set I²C address, dimming curves, or protection thresholds). This is performed by MPS during final test; customers request custom OTP via part number suffix (e.g., MP3320BGG-Z-OTPxx). Standard MP3320BGG-Z units ship with default values per register map (Rev. 1.0, p.15), and OTP programming is irreversible.