Monolithic Power Systems Inc. MPQ4436AGRE-Z

Overview

MPQ4436AGRE-Z from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, synchronous step-down DC/DC converter with integrated 48mΩ high-side and 20mΩ low-side MOSFETs, delivering up to 6A output current across a 3.3V–45V input range. It features 1.7μA shutdown quiescent current, configurable 350–1000kHz switching frequency, and power-good (PG) monitoring - optimized for automotive infotainment and ADAS power rails.

For engineers reviewing the MPQ4436AGRE-Z datasheet, MPQ4436AGRE-Z pinout, MPQ4436AGRE-Z application, or MPQ4436AGRE-Z equivalent, this device supports critical design requirements including cold-crank operation (low-dropout mode), EMI reduction via frequency spread spectrum (FSS), and precise output regulation (±2% for 5V version) in space-constrained automotive modules.

Technical Context

The MPQ4436AGRE-Z employs current-mode control with fast transient response and integrates both power switches, eliminating external FETs. Its adaptive modulation supports Advanced Asynchronous Modulation (AAM) for light-load efficiency and Forced Continuous Conduction Mode (FCCM) for fixed-frequency noise predictability.

It implements frequency foldback at startup to prevent inductor current runaway, thermal shutdown at 170°C with 20°C hysteresis, and hiccup-mode over-current protection. The device synchronizes to external clocks (350–1000kHz) and provides out-of-phase SYNC output for multi-rail phase interleaving.

Key Specifications

Pinout & Package

MPQ4436AGRE-Z is housed in a wettable-flank QFN-20 package (4mm × 4mm, 0.5mm pitch), enabling automated optical inspection (AOI) and robust solder joint reliability for automotive reflow processes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4436AGRE-Z, MPQ4433AGRE-AEC1-Z offers identical automotive qualification and footprint but trades 6A capability for lower cost, while TPS546B24RVFT adds digital control at the expense of automotive compliance and input voltage flexibility.

Availability

MPQ4436AGRE-Z is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and instrument cluster designs requiring stable component supply with AEC-Q100 Grade 1 assurance and wettable flank manufacturability.

Supply support for MPQ4436AGRE-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 core expertise in DC/DC converters, LED drivers, and motor drivers.

The MPQ4436A belongs to MPS's automotive-grade synchronous buck converter product line, engineered specifically for harsh-temperature, high-reliability vehicle subsystems including infotainment, ADAS, and body electronics.

FAQ

What is the maximum allowable input voltage for MPQ4436AGRE-Z?

The absolute maximum input voltage is +50V, but the recommended operating range is 3.3V to 45V. Exceeding 45V may trigger overvoltage protection or degrade long-term reliability, especially under high-temperature conditions. The device is designed for automotive battery environments, including load-dump transients up to 45V.

Does MPQ4436AGRE-Z require an external bootstrap capacitor?

Yes - a 0.1μF ceramic capacitor must be placed between BST and SW pins. This capacitor supplies gate drive energy for the high-side MOSFET during each switching cycle. Incorrect sizing or placement can cause gate drive failure, leading to erratic operation or thermal shutdown.

How does the MODE pin affect efficiency and noise performance?

When MODE is pulled low, the device enters Advanced Asynchronous Modulation (AAM), skipping pulses at light loads to reduce switching losses and achieve >85% efficiency at 1mA. When pulled high, it operates in Forced Continuous Conduction Mode (FCCM), maintaining constant frequency for predictable EMI and minimal output ripple - ideal for noise-sensitive analog circuits.

Can MPQ4436AGRE-Z be synchronized to an external clock source?

Yes - apply a 350kHz–1000kHz square wave to the SYNCIN pin. The internal oscillator locks to this signal, enabling precise timing alignment across multiple rails. Unused SYNCIN must be tied to GND; floating it risks erratic frequency behavior and increased EMI.

What is the purpose of the NC pin (Pin 15), and how should it be handled?

Pin 15 is not internally connected but must be tied to VCC or VOUT (≥3V) - never left floating. Leaving it unconnected can induce latch-up or unpredictable startup behavior due to internal floating node coupling. This requirement is explicitly defined in the datasheet's Absolute Maximum Ratings section.

Is MPQ4436AGRE-Z compatible with standard QFN reflow profiles?

Yes - it follows JEDEC J-STD-020D moisture sensitivity level 1 (MSL 1) and supports standard lead-free reflow profiles. The wettable flank design allows post-solder AOI inspection of side-solder joints, meeting IPC-A-610 Class 3 automotive acceptance criteria without requiring X-ray verification.

How does the power-good (PG) signal behave during undervoltage and overvoltage conditions?

PG goes low when FB voltage falls below 93.5% or rises above 106.5% of nominal output; it asserts high only when FB is within 95–105%. The 35μs propagation delay ensures clean sequencing with downstream regulators and MCUs, and the open-drain structure requires an external pull-up resistor to a valid supply rail.