Monolithic Power Systems Inc. MPQ2325GJ-P

Overview

MPQ2325GJ-P from Monolithic Power Systems is a synchronous step-down DC/DC converter with integrated 90mΩ high-side and 40mΩ low-side MOSFETs, delivering 3A continuous output current across a 4.5V–24V input range. It operates at a fixed 500kHz switching frequency with power-save mode for light loads, internal soft-start, and power-good indication-designed for compact, high-efficiency point-of-load regulation in space-constrained I/O power rails.

For engineers reviewing the MPQ2325GJ-P datasheet, MPQ2325GJ-P pinout, MPQ2325GJ-P application, or MPQ2325GJ-P equivalent, key selection criteria include its TSOT23-8 package footprint, 0.8V feedback reference, 150°C thermal shutdown threshold, and EN/SYNC dual-function pin supporting external clock synchronization from 200kHz to 2MHz.

Technical Context

The MPQ2325GJ-P uses peak-current-mode control with an internal 0.8V reference and optimized compensation network, enabling stable regulation without external loop components. Its cycle-by-cycle over-current protection triggers hiccup mode under sustained overload, while the bootstrap driver supports high-duty-cycle operation via external BST capacitor and optional diode.

It integrates a 5V internal regulator powered from VIN, with UVLO thresholds at 3.9V (rising) and 3.25V (falling), and implements asynchronous modulation (AAM) for light-load efficiency-reducing switching frequency below 500kHz when V_COMP falls below the AAM threshold to maintain constant inductor peak current (~500mA at 3.3V/12V).

Key Specifications

Pinout & Package

MPQ2325GJ-P is housed in a thermally enhanced, space-saving TSOT23-8 package (2.9mm × 1.6mm × 0.85mm), with exposed pad for improved heat dissipation and JEDEC MO-193BA compliance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ2325GJ-P, MP2325GJ-Z offers identical performance in tape-and-reel form, while RT7295BGJ8F trades SYNC and precision 0.8V feedback for higher input voltage tolerance-making MPQ2325GJ-P optimal for compact, noise-sensitive, multi-rail designs needing precise low-voltage outputs and clock coordination.

Availability

MPQ2325GJ-P is available at Aetrix Electronics and suitable for notebook I/O power, digital set-top box SoC supplies, and flat-panel monitor logic boards requiring stable component supply, consistent parametric performance, and long-term manufacturability.

Supply support for MPQ2325GJ-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 emphasis on energy-efficient DC/DC conversion, motor drivers, and LED lighting solutions.

The MPQ2325 belongs to MPS's MPQ-series of integrated synchronous buck converters, designed specifically for space-constrained, high-current point-of-load applications in consumer, computing, and industrial electronics where thermal performance and EMI control are critical.

FAQ

What is the maximum recommended PCB copper area for the exposed pad of MPQ2325GJ-P?

The TSOT23-8 package includes an exposed thermal pad that must be soldered to a minimum 25 mm² copper pour with ≥4 thermal vias (0.3mm diameter) connecting to inner ground planes. This configuration achieves θ_JA ≈ 100°C/W per JEDEC JESD51-7 4-layer test board, enabling full 3A operation at +85°C ambient.

Can MPQ2325GJ-P operate with an input voltage below 4.5V?

No-MPQ2325GJ-P has a hard UVLO threshold of 3.9V (rising) and will not start or regulate below 4.5V input. Attempting operation below this causes intermittent enable/disable cycling and potential instability. For sub-4.5V inputs, consider MPS's MP2451 (2.5–6V input) or MP2315 (4.2–17V with lower current).

How does the EN/SYNC pin behave during external clock synchronization?

When an external clock is applied to EN/SYNC, the MPQ2325GJ-P locks its internal oscillator to the rising edge of that clock after ~2ms stabilization. The pin must receive logic-high >2V and logic-low <400mV, with pulse widths <1.6μs (high) and <6μs (low); exceeding these risks unintended enable/disable or hiccup entry.

What is the purpose of the frequency foldback function triggered by low FB voltage?

When FB drops below 400mV (e.g., during output short-circuit), the MPQ2325GJ-P reduces switching frequency to ~250kHz (0.5×f_SW) to limit peak inductor current and average power dissipation. This foldback works with hiccup-mode OCP to sustain safe thermal operation during fault conditions without requiring external circuitry.

Is an external bootstrap diode required for reliable operation?

An external bootstrap diode (e.g., 1N4148) is optional but recommended when duty cycle exceeds 65%-such as in 5V-out-from-19V-in configurations-to prevent BST capacitor discharge through the internal LDO path. Without it, efficiency drops ~2–3% and BST voltage may dip below 2.2V UVLO threshold under heavy load.

Does MPQ2325GJ-P support adjustable soft-start time via external capacitor?

No-the soft-start period is fixed internally at ~1.5ms (0.5–2.7ms over temperature). There is no external SS pin or capacitor option. The internal ramp generator charges a dedicated on-chip capacitor; designers must rely on this fixed timing for inrush control and cannot extend or shorten it.

What is the minimum output capacitance required for stable regulation?

Stable operation requires ≥22μF total output capacitance with ≤10mΩ ESR (e.g., X5R/X7R ceramic). Lower values risk loop instability and excessive ripple-especially with high-frequency ceramic caps lacking sufficient bulk capacitance. The datasheet validates stability with 44μF (2×22μF) in typical applications.