Monolithic Power Systems Inc. MP4323GDE-P

Overview

MP4323GDE-P from Monolithic Power Systems is a 42V load-dump-tolerant, 3A synchronous step-down DC/DC converter with integrated 70mΩ high-side and 50mΩ low-side MOSFETs, 3.3V–36V input range, and 1μA shutdown current-designed for automotive power rails in USB chargers and battery-powered systems.

For engineers reviewing the MP4323GDE-P datasheet, MP4323GDE-P pinout, MP4323GDE-P application, or MP4323GDE-P equivalent, key selection criteria include 42V transient tolerance, QFN-12 (2mm×3mm) wettable flank package, CISPR25 Class 5 EMI compliance, and configurable 350kHz–2.5MHz switching frequency with spread-spectrum modulation.

Technical Context

The MP4323GDE-P employs peak current-mode control with frequency foldback during startup to prevent inductor current runaway. It integrates advanced asynchronous modulation (AAM) for light-load efficiency and supports low-dropout mode down to 3.1V VIN for cold-crank operation.

Its dual VIN pins (pins 2 & 10), symmetric layout, and MeshConnect™ flip-chip packaging reduce EMI; FSS modulation and configurable fSW enable robust CISPR25 Class 5 compliance across 150kHz–1GHz radiated and conducted bands.

Key Specifications

Pinout & Package

MP4323GDE-P is housed in a wettable flank QFN-12 (2mm × 3mm) package with exposed thermal pad, optimized for automated optical inspection (AOI) and thermal performance (θJA = 35.5°C/W on 4-layer EV board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with LM61480RQWR and TPS62933RTER, MP4323GDE-P uniquely combines 42V load dump tolerance, wettable flank QFN-12 packaging, and CISPR25 Class 5 compliance in a 3A solution-making it optimal for space-constrained, safety-critical automotive power rails where transient resilience and manufacturability are co-priorities.

Availability

MP4323GDE-P is available at Aetrix Electronics and suitable for automotive USB charging, ADAS camera power supplies, telematics control units, and infotainment core rails requiring stable component supply across extended temperature and transient conditions.

Supply support for MP4323GDE-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 power management ICs, with over two decades of innovation in DC/DC converters, motor drivers, and LED drivers.

The MP4323 belongs to MPS's automotive-grade buck converter product line, engineered specifically for harsh-environment applications demanding ISO16750 compliance, extended temperature operation (–40°C to +125°C), and high-density integration.

FAQ

What is the minimum input voltage required to start up the MP4323GDE-P?

The MP4323GDE-P has a VIN UVLO rising threshold of 3.65V (typical), meaning it requires at least 3.65V on the VIN pin to initiate startup. After startup, it sustains regulation down to 3.1V VIN, supporting automotive cold-crank conditions per ISO16750-2.

How does the frequency spread spectrum (FSS) function improve EMI performance?

FSS modulates the switching frequency by ±10% at 15kHz, spreading energy across a bandwidth instead of concentrating it at harmonics. This reduces peak radiated and conducted emissions, enabling MP4323GDE-P to meet CISPR25 Class 5 limits without additional filtering components.

Can the MP4323GDE-P operate with a fixed output voltage without external feedback resistors?

No-the MP4323GDE-P is the adjustable-output version. Fixed-output variants (e.g., MP4323AGDE-P) exist but require separate ordering. For MP4323GDE-P, FB must be connected to an external resistor divider to set VOUT; direct connection to VOUT yields undefined regulation.

What is the purpose of the dual VIN pins (pins 2 and 10)?

Pins 2 and 10 are internally connected VIN inputs that reduce parasitic inductance in the high-current input path. This dual-pin layout minimizes voltage spikes during switching transitions and improves EMI performance-especially critical for CISPR25 Class 5 compliance in automotive applications.

Is the wettable flank QFN-12 package compatible with standard reflow profiles?

Yes-the MP4323GDE-P's wettable flank QFN-12 package is designed for standard lead-free reflow (J-STD-020). The side-wettable leads enable automated optical inspection (AOI) of solder joints, improving manufacturing yield and reliability verification in automotive production lines.

Does the PG pin require an external pull-up resistor?

Yes-the PG pin is open-drain and must be pulled up externally (typically to VOUT or VCC) with a resistor between 10kΩ and 100kΩ. Without a pull-up, PG remains floating and cannot assert valid power-good status to downstream logic or microcontrollers.

How does the low-dropout (LDO) mode function during cold-crank events?

In low-dropout mode, the MP4323GDE-P increases duty cycle beyond normal limits (up to 99.5%) to maintain regulation when VIN drops near VOUT. This allows continued operation down to VIN = 3.1V while delivering full 3A load-critical for engine-start sequences where battery voltage sags below 6V.