Monolithic Power Systems Inc. MP4255GVE-0001-Z

Overview

MP4255GVE-0001-Z from Monolithic Power Systems is a dual-channel, monolithic synchronous buck converter IC with digital I²C interface and OTP programming, designed for USB Power Delivery (PD) 3.1 applications. It delivers up to 3A per channel (or shared 6A) across 4V–36V input, supports 1V–21V digitally adjustable output voltage, integrates 22mΩ/26mΩ internal MOSFETs, and operates at selectable switching frequencies (250kHz–2.1MHz) in a wettable-flank QFN-21 (4mm×5mm) package.

For engineers reviewing the MP4255GVE-0001-Z datasheet, MP4255GVE-0001-Z pinout, MP4255GVE-0001-Z application in USB PD chargers, or MP4255GVE-0001-Z equivalent for dual-buck power delivery, this page provides verified technical context, validated pin functions, confirmed protection features (OCP/OVP/thermal shutdown), real-world efficiency curves, and design-meaningful specifications - all extracted from the official MP4255 Rev. 1.0 datasheet.

Technical Context

The MP4255 implements two independent peak-current-mode synchronous buck regulators with fixed-frequency PWM control, each driven by a dedicated oscillator with programmable phase delay. Its digital interface enables real-time adjustment of VOUT (1V–21V), IOUT_LIMIT (50mA steps), fSW (four discrete settings), FSS, line drop compensation, and PFM/PWM mode selection via I²C.

It integrates dual bootstrap regulators (BST1/BST2), an internal 5V VCC LDO with BIAS-pin-assisted efficiency optimization, bus-voltage isolation gate drivers (GATE1/GATE2), and a dedicated alert pin (ALT) for load-shedding events. The device uses internal error amplifiers with optimized compensation and supports LDO-mode operation for ultra-low dropout at high duty cycles.

Key Specifications

Pinout & Package

MP4255GVE-0001-Z is housed in a thermally enhanced, lead-free, wettable-flank QFN-21 package (4mm × 5mm, 0.5mm pitch), optimized for high-power density USB PD designs with exposed thermal pad (PGND-connected) and AOI-compatible edge plating.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel buck converter applications.

Compared with MPQ4425HGQ-AEC1-P, MP4255GVE-0001-Z adds real-time digital control and OTP flexibility at the cost of AEC-Q100 certification; versus TPS65987D, it provides complete power conversion capability rather than protocol-only functionality - making it the sole choice for self-contained dual-buck PD power stages.

Availability

MP4255GVE-0001-Z is available at Aetrix Electronics and suitable for USB-C PD charger development, industrial USB power management, and programmable lab power supply modules requiring stable component supply, guaranteed OTP configuration, and wettable-flank QFN packaging for high-yield manufacturing.

Supply support for MP4255GVE-0001-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 over 20 years of expertise in DC/DC conversion, motor drivers, and battery management solutions.

The MP4255 belongs to MPS's USB Power Delivery power stage product line, engineered specifically to integrate dual high-current buck regulation, digital configurability, and robust protection into a single chip for next-generation compact, intelligent USB-C chargers and adapters.

FAQ

What is the function of the BIAS pin on MP4255GVE-0001-Z?

The BIAS pin supplies an external 5V–9V voltage to enable a secondary internal LDO (LDO2), which powers the IC when VIN drops below 5V. Connecting BIAS to VOUT improves light-load efficiency by bypassing the main VIN-powered LDO1. An RC low-pass filter is required between BIAS and VOUT to suppress noise.

Can MP4255GVE-0001-Z support output voltages above 21V?

No - the digital interface limits VOUT commands to ≤21V. For higher outputs (e.g., 24V), the feedback resistor divider must be manually configured to scale VFB, bypassing the internal DAC. This requires hardware modification and forfeits digital reprogrammability for that channel.

How does the ALT pin behave during over-current events?

The ALT pin is an open-drain output pulled low during OCP, OVP, or thermal shutdown. It remains asserted until the fault condition clears and the device recovers - providing immediate hardware-level alert to host MCU without polling I²C registers.

What is the minimum off-time specification, and why does it matter?

The minimum off-time is 100ns. This limits the maximum achievable duty cycle at high switching frequencies - e.g., at 2.1MHz, DMAX is ~85%. It constrains the lowest input-to-output voltage ratio usable in PWM mode, making LDO mode essential for high-VIN/low-VOUT applications.

Is MP4255GVE-0001-Z pin-compatible with other MP4255 variants?

Yes - all MP4255GVE-xxxx variants share identical QFN-21 pinout, thermal pad layout, and electrical characteristics. The "0001" suffix denotes a factory-programmed OTP configuration (e.g., default 420kHz fSW, 5V/9V VOUT presets); no hardware changes are needed when swapping configurations.

Does MP4255GVE-0001-Z support forced PWM mode across all loads?

Yes - the digital interface allows disabling PFM mode to enforce continuous PWM operation regardless of load. This eliminates audible switching noise and ensures predictable EMI profiles during transient testing and compliance validation.

What thermal performance can be expected on a standard 4-layer PCB?

On the EV4255-VE-00A evaluation board (55mm×55mm, 4-layer), case temperature rise is ≤35°C at 3A/channel (6A total) with VIN=12V and fSW=420kHz. θJA is 24.6°C/W - confirming suitability for enclosed USB charger enclosures without active cooling.