Monolithic Power Systems Inc. MP2388GQEU-Z

Overview

MP2388GQEU-Z from Monolithic Power Systems is a synchronous step-down DC/DC converter IC with integrated 110mΩ high-side and 50mΩ low-side MOSFETs, delivering 1A continuous output current across a 4.5V–21V input range. It operates at a fixed 2MHz switching frequency, supports adjustable output down to 0.8V, and integrates AAM power-save mode for light-load efficiency-used in compact I/O power rails for notebooks and flat-panel displays.

For engineers reviewing the MP2388GQEU-Z datasheet, MP2388GQEU-Z pinout, MP2388GQEU-Z application, or MP2388GQEU-Z equivalent, key selection criteria include its ultra-thin QFN-8 (1.5mm×2.5mm) footprint, thermal shutdown at 150°C, 798mV feedback reference voltage, cycle-by-cycle over-current protection with hiccup recovery, and bootstrap-driven high-side gate drive requiring external BST capacitor and diode.

Technical Context

The MP2388GQEU-Z employs peak-current-mode control with internal compensation, enabling stable regulation without external loop components. Its 2MHz fixed-frequency operation allows use of small 1µH inductors and ceramic capacitors, reducing solution size while maintaining <15mV output ripple in typical 3.3V/1A designs.

It features dual-stage protection: over-current limit triggers hiccup mode upon sustained short-circuit, and thermal shutdown disables all circuitry above 150°C with 20°C hysteresis. The AAM pin enables programmable transition between PWM and PFM modes via an external resistor, optimizing efficiency across 10mA–1A load range.

Key Specifications

Pinout & Package

MP2388GQEU-Z is housed in an ultra-thin QFN-8 package (1.5mm × 2.5mm, 0.5mm height), with wettable flanks and exposed thermal pad for enhanced PCB heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2388GQEU-Z, MP2315GJ-Z trades current capability and AAM for smaller size and higher frequency, while TPS561201DRCT offers greater current and SOIC reliability at the cost of solution size and light-load efficiency-making MP2388GQEU-Z optimal for space-constrained 1A applications demanding full-load efficiency and intelligent light-load management.

Availability

MP2388GQEU-Z is available at Aetrix Electronics and suitable for notebook I/O power, digital set-top box core rails, and flat-panel monitor logic supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP2388GQEU-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 analog and power ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MP2388 belongs to MPS's high-frequency synchronous buck converter product line, engineered for space-constrained portable and consumer electronics where ultra-thin packaging, high efficiency across load range, and minimal external component count are critical.

FAQ

What is the minimum recommended input capacitance for MP2388GQEU-Z?

A 22µF X5R/X7R ceramic capacitor is recommended for most applications, placed as close as possible to the IN and GND pins. This value provides adequate RMS current handling and limits input voltage ripple to <100mV under 1A load at 2MHz switching. A 0.1µF ceramic capacitor in parallel further suppresses high-frequency noise.

Can MP2388GQEU-Z operate with a 3.3V input supply?

No. The absolute minimum input voltage is 4.5V per the Recommended Operating Conditions table. At 3.3V, the internal VCC regulator cannot sustain 5V bias, causing functional failure. The under-voltage lockout (UVLO) rising threshold is 3.9V, so operation below 4.5V is neither guaranteed nor supported.

How is the AAM pin used to improve light-load efficiency?

The AAM pin accepts a resistor to ground that sets a voltage threshold (VAAM = 6.2µA × RAAM). When the error amplifier output (VCOMP) falls below VAAM and FB < 0.798V, the internal clock is blocked, entering PFM mode. This reduces switching losses and lowers quiescent current to 0.2mA, boosting efficiency from ~65% to >85% at 10mA load.

Is an external bootstrap diode required for MP2388GQEU-Z?

An external bootstrap diode (e.g., IN4148) from VCC to BST is optional but recommended when duty cycle exceeds 65%-such as in 5V or 3.3V outputs from 12V–19V inputs. It improves BST capacitor charging efficiency, stabilizes high-side gate drive, and prevents dropout during heavy load transients.

What is the thermal resistance (θ_JA) of the QFN-8 package under standard JEDEC conditions?

The junction-to-ambient thermal resistance θ_JA is 100°C/W, measured on a 4-layer JEDEC-standard PCB (JESD51-7). This value assumes proper thermal pad soldering to a 100mm² copper pour with ≥4 thermal vias. Without adequate copper, θ_JA may exceed 130°C/W, limiting maximum continuous output current to ~750mA at +85°C ambient.

Does MP2388GQEU-Z support output voltages below 0.8V?

No. The internal feedback reference is fixed at 798mV ±12mV, and the datasheet specifies "Output Adjustable from 0.8V" as the minimum regulated output. Attempting to set lower voltages via resistor divider violates the FB pin's valid operating range and results in loss of regulation and potential instability.

How does the hiccup-mode over-current protection behave during a sustained short circuit?

Upon current-limit detection, MP2388GQEU-Z disables switching and waits ~500ms before attempting restart. If the short persists, it repeats the cycle-limiting average power dissipation to <0.5W. This prevents thermal runaway while allowing automatic recovery when the fault clears, unlike latch-off protection which requires manual reset or power cycle.