Monolithic Power Systems Inc. MP4568GQ-P

Overview

MP4568GQ-P from Monolithic Power Systems is a 60V-input, 100mA synchronous step-down DC/DC converter with integrated high-side (2.25Ω) and low-side (0.7Ω) MOSFETs, 1.0V feedback reference, programmable peak current limit (55–260mA), and 5μA shutdown quiescent current. It operates across 4.5V–45V input range and delivers stable output for automotive sensor power rails and industrial 4–20mA loop supplies.

For engineers reviewing the MP4568GQ-P datasheet, MP4568GQ-P pinout, MP4568GQ-P application, or MP4568GQ-P equivalent, key selection criteria include its 60V MOSFET rating, ceramic-capacitor compatibility, adjustable UVLO hysteresis via EN/ENHY, soft-start timing control via external SS capacitor, and precision current-limit programming without sense resistors.

Technical Context

The MP4568GQ-P uses peak-current-mode PWM control with zero-current detection (ZCD) to regulate output voltage by comparing FB voltage against a 1.0V internal reference and limiting inductor current via ILIM-pin-programmable thresholds. Its adaptive frequency scaling under light load reduces switching and gate-driver losses while maintaining >90% efficiency at 10V_IN/5V_OUT/2mA.

It integrates a bootstrap regulator that charges the BST–SW capacitor to ~5V during low-side conduction, enabling high-side MOSFET drive; BIAS pin operation above 4.5V powers both internal circuitry and the low-side driver, improving conversion efficiency. Thermal shutdown activates at 160°C with 20°C hysteresis, and EN pin logic is HIGH-active with 1.6V rising threshold and 1.2V falling threshold.

Key Specifications

Pinout & Package

MP4568GQ-P is housed in a thermally enhanced 3mm × 3mm QFN10 package with exposed thermal pad (pin 3 GND). The package supports high-power-density layouts and requires controlled-impedance routing for SW and BST nodes to minimize EMI.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4568GQ-P, the MP4568GQ-P trades automotive qualification for lower cost and faster lead time; versus LMR36520RNXR, it provides finer current-limit tuning and deeper shutdown, making it optimal for battery-sensitive, programmable industrial power nodes.

Availability

MP4568GQ-P is available at Aetrix Electronics and suitable for automotive sensor power supplies, industrial 4–20mA loop transmitters, and distributed battery-powered nodes requiring stable component supply across design-in, prototyping, and volume production phases.

Supply support for MP4568GQ-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 core expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MP4568 belongs to MPS's high-voltage synchronous buck converter product line, designed specifically for ruggedized industrial and automotive subsystems where input transients, low quiescent current, and integration density are critical.

FAQ

What is the minimum input voltage required for MP4568GQ-P to start switching?

The MP4568GQ-P begins operation when VIN exceeds the UVLO rising threshold of 4.2V (typical). Below this, the device remains in shutdown regardless of EN state. Once enabled, it sustains regulation down to 4.5V per datasheet operating conditions, with internal regulator functionality maintained above 3.0V.

Can the MP4568GQ-P drive a 100mA load continuously at 45V input?

Yes, but thermal design is critical: at 45V_IN/5V_OUT/100mA, power dissipation reaches ~1.2W. With θ_JA = 50°C/W, junction temperature rise is ~60°C above ambient. A 2-layer PCB with 200mm² copper pour on GND pad keeps T_J within 125°C limit at 25°C ambient.

How does the ENHY pin function in UVLO configuration?

ENHY is an open-drain output that pulls low when EN voltage drops below 1.2V. When used with external resistors (e.g., R6 between ENHY and EN), it lowers the UVLO falling threshold independently of the rising threshold-enabling asymmetric hysteresis for stable brown-out recovery without oscillation.

Is the 1.0V feedback reference internally trimmed for accuracy?

Yes-the FB reference voltage is specified as 0.99V to 1.01V (±1%) over temperature and line, measured at TJ = 25°C with VIN = 4.5V to 45V. This tight tolerance enables output voltage accuracy better than ±2% using standard 1% resistors in the feedback divider.

What happens to the SS pin during thermal shutdown?

During thermal shutdown, the SS voltage resets to 0V. Upon recovery-when junction temperature falls below the hysteresis threshold-the soft-start sequence restarts from zero, ensuring controlled output ramp-up and preventing overshoot after fault clearance.

Does the BIAS pin require external capacitance?

No external capacitor is required on BIAS. However, if BIAS is connected to VOUT (e.g., 3.3V or 5V), ensure the output rail has sufficient bulk capacitance (≥22μF) to prevent BIAS droop during load transients, which could disrupt low-side driver operation.

Can the MP4568GQ-P operate without the BST capacitor?

No-the BST capacitor (0.1μF ceramic) between BST and SW is mandatory. Without it, the high-side MOSFET cannot be driven, causing immediate failure of regulation and potential damage due to shoot-through or uncontrolled switching.