Monolithic Power Systems Inc. MPQ4568GQ-P

Overview

MPQ4568GQ-P from Monolithic Power Systems is a synchronous step-down DC/DC converter IC with integrated 60V high-side/low-side MOSFETs, delivering up to 100mA output current at >90% efficiency (10V_IN→5V_OUT/2mA), featuring 1.0V feedback reference, programmable peak current limit (55–260mA), and 5μA shutdown quiescent current. It operates across 4.5V–45V input range and targets industrial and automotive power rails where wide VIN, low IQ, and thermal robustness are critical.

For engineers reviewing the MPQ4568GQ-P datasheet, MPQ4568GQ-P pinout, MPQ4568GQ-P application, or MPQ4568GQ-P equivalent, key selection criteria include its 60V MOSFET rating, QFN10 (3×3mm) package thermal performance (θ_JA = 50°C/W), adjustable UVLO hysteresis via EN/ENHY, and ceramic-capacitor-compatible control architecture enabling compact, low-ripple 4–20mA loop supplies.

Technical Context

The MPQ4568GQ-P implements a current-mode PWM controller with zero-current detection (ZCD) and internal 1V reference, enabling precise regulation and fast load transient response. Its dual-MOSFET topology integrates a 0.7Ω low-side and 2.25Ω high-side switch, supporting synchronous rectification without external diodes.

Operation includes adaptive frequency scaling under light load to reduce switching losses, programmable soft-start via external capacitor on SS pin, and bootstrap-driven high-side gate drive with dedicated BST-SW bypass capacitor. Thermal shutdown activates at 160°C with 20°C hysteresis, and EN pin enables HIGH-active logic with internal 2MΩ pull-down.

Key Specifications

Pinout & Package

MPQ4568GQ-P is housed in a thermally enhanced 3mm × 3mm QFN10 package with exposed thermal pad (pin 3 GND connected to pad), supporting PCB copper pour for θ_JA = 50°C/W on 4-layer board per JESD51-7.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4568GQ-P, MPQ4572GQ-P trades ultra-low IQ for higher output current, while LMR36015QRNXTQ1 adds automotive qualification and excessive current headroom at the expense of cost, footprint, and unnecessary complexity for 100mA industrial applications.

Availability

MPQ4568GQ-P is available at Aetrix Electronics and suitable for 4–20mA current loops, automotive cabin sensors, and battery-powered remote I/O modules requiring stable component supply across extended temperature and long-lifecycle programs.

Supply support for MPQ4568GQ-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 analog and power ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ4568 belongs to MPS's industrial-grade synchronous buck converter product line, engineered specifically for ruggedized 4.5–45V input applications in harsh environments including factory automation, process control, and automotive body electronics.

FAQ

What is the minimum input voltage required for MPQ4568GQ-P to regulate?

The MPQ4568GQ-P begins regulation at VIN ≥ 4.5V, defined by its rising UVLO threshold of 4.0V (min 3.75V). Below this, the device remains in shutdown with <5μA current draw. The internal 2.6V regulator requires VIN > 3.0V for partial functionality, but full regulation and switching commence only above 4.5V.

Can MPQ4568GQ-P operate with an output voltage lower than 1.0V?

No - the internal feedback reference is fixed at 1.0V, and the FB pin compares the resistive divider output against this reference. Output voltages below 1.0V cannot be regulated; the lowest supported output is 1.0V (achieved with R2 = 0Ω, R1 open), though practical designs start at 1.2V due to resistor tolerance and noise margins.

How does the BIAS pin improve efficiency?

When VBIAS ≥ 2.9V, the BIAS pin powers the internal 2.6V regulator instead of VIN, reducing dropout loss. At VBIAS ≥ 4.5V, it also powers the low-side MOSFET driver directly, eliminating gate-drive current draw from VIN. This typically improves full-load efficiency by 1–2% when BIAS is tied to a clean, regulated VOUT.

What is the purpose of the ENHY pin beyond UVLO hysteresis?

ENHY is an open-drain indicator that sinks current only when EN falls below its 1.2V falling threshold. Beyond UVLO hysteresis extension, it can drive status LEDs, enable secondary regulators, or signal microcontroller wake-up interrupts - providing a system-level fault flag independent of the main EN logic state.

Is the MPQ4568GQ-P RoHS-compliant and lead-free?

Yes - MPQ4568GQ-P is fully RoHS-compliant and lead-free, with all package finishes meeting JEDEC J-STD-609 Category 1 requirements. MPS confirms green status on its official website under Products > Quality Assurance, and the QFN10 package uses matte tin plating over copper leadframe.

Why does the datasheet specify "ILIM floating = 55mA" but list min peak current as 30mA?

The 30mA value is the electrical characteristic minimum measured under test conditions (TJ = –40°C to +125°C), while "ILIM floating = 55mA" reflects the typical design condition when the pin is left unconnected. The 30mA lower bound accounts for process variation and temperature extremes - designers should use 55mA as the nominal floating setting and verify worst-case current limit at end-of-life conditions.

Does MPQ4568GQ-P support forced PWM mode?

No - MPQ4568GQ-P uses adaptive frequency scaling (pulse-frequency modulation) under light load to minimize switching losses. It lacks a MODE pin or register to force continuous PWM operation; frequency reduction is inherent to its ZCD-based control architecture and cannot be disabled.