Monolithic Power Systems Inc. MP2225GJ-Z

Overview

MP2225GJ-Z from Monolithic Power Systems is a synchronous step-down DC/DC converter with integrated 47mΩ high-side and 18mΩ low-side MOSFETs, delivering up to 5A output current across a 4.5V–18V input range. It operates at a fixed 500kHz switching frequency (synchronizable from 200kHz to 2MHz), features 1% reference accuracy at room temperature, and includes hiccup-mode over-current protection and thermal shutdown. It is used in notebook I/O power rails where compact size and high efficiency (>97%) are critical.

For engineers reviewing the MP2225GJ-Z datasheet, MP2225GJ-Z pinout, MP2225GJ-Z application, or MP2225GJ-Z equivalent, this page provides verified technical context, validated pin functions, confirmed operating parameters, and real-world application implementation details for embedded power design and BOM validation.

Technical Context

The MP2225GJ-Z uses peak-current-mode control with an internal 500kHz oscillator and supports external clock synchronization (200kHz–2MHz) via the EN/SYNC pin. Its AAM (Advanced Asynchronous Modulation) enables light-load PFM operation with internally set ~800mA inductor peak current threshold.

It integrates a 5V internal VCC regulator powered from VIN, bootstrap charging circuitry with UVLO (2.6V rising threshold), and a precision error amplifier comparing FB voltage against a 0.6V reference. The cycle-by-cycle over-current limit triggers hiccup mode when FB drops below ~30% of VREF during sustained overload or short-circuit conditions.

Key Specifications

Pinout & Package

MP2225GJ-Z is housed in an 8-pin TSOT23 package - a space-constrained, thermally enhanced surface-mount outline optimized for high-density PCB layouts in portable and embedded systems.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2225GJ-Z, MP2235GJ-Z offers direct pin-compatible headroom for higher current, while TPS54560QDGQRQ1 trades compactness and cost for automotive qualification and ultra-wide input range-neither is a drop-in replacement outside their specific use cases.

Availability

MP2225GJ-Z is available at Aetrix Electronics and suitable for flat-panel television power supplies, notebook I/O subsystems, digital set-top boxes, and distributed telecom power modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MP2225GJ-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.

The MP2225 belongs to MPS's high-efficiency DC/DC converter product line, engineered for space-constrained consumer and computing applications requiring minimal external components and robust protection.

FAQ

What is the minimum recommended output voltage for MP2225GJ-Z?

The MP2225GJ-Z supports adjustable output voltages as low as 0.6V, set by the external resistor divider connected to the FB pin. This 0.6V reference enables regulation of modern low-voltage SoC cores and memory interfaces, and the 1% accuracy at 25°C ensures tight tolerance across temperature and load.

Can MP2225GJ-Z synchronize to an external clock, and what is the valid frequency range?

Yes - the EN/SYNC pin accepts an external clock signal from 200kHz to 2MHz. The internal oscillator synchronizes to the rising edge of that signal, provided the high- and low-time durations exceed 250ns and 100ns respectively. This feature enables EMI reduction through frequency dithering or system-level clock alignment.

Does MP2225GJ-Z require an external bootstrap diode?

An external bootstrap diode (e.g., 1N4148) is optional and recommended only under specific conditions: when VIN < 5V *and* duty cycle > 65%, or when VIN − VOUT < 2.6V. In standard 12V-to-3.3V operation, the internal bootstrap circuit suffices; the diode improves light-load efficiency and reduces output ripple in marginal BST voltage scenarios.

How does the hiccup-mode over-current protection operate?

When output current exceeds the cycle-by-cycle limit (~6.5–9A), the MP2225GJ-Z enters hiccup mode if FB voltage drops below ~30% of the 0.6V reference (i.e., ~180mV) for a sustained period. It then shuts down, waits ~10ms, and attempts restart - limiting average short-circuit current and die temperature until the fault clears.

What is the thermal resistance (θ_JA) of the TSOT23-8 package under standard JEDEC conditions?

The junction-to-ambient thermal resistance θ_JA for MP2225GJ-Z in TSOT23-8 is 100°C/W, measured per JESD51-7 on a 4-layer PCB. This value assumes proper PCB layout: wide copper pours on GND and IN pins, multiple thermal vias under the exposed pad (if present), and adequate airflow - actual performance depends on board-specific thermal design.

Is MP2225GJ-Z RoHS-compliant and lead-free?

Yes - MP2225GJ-Z is fully RoHS-compliant and lead-free, consistent with MPS's green manufacturing policy. All packaging materials and die attach meet EU Directive 2011/65/EU requirements, and full compliance documentation is available on the MPS Quality Assurance webpage.

What is the maximum duty cycle limitation, and how does it affect minimum output voltage at high input?

The MP2225GJ-Z has a maximum duty cycle of 90–95%, limiting the lowest achievable output voltage at high input. For example, at VIN = 18V, the practical minimum VOUT is ~1.6V–1.8V (90% × 18V = 16.2V max, but regulation requires headroom). To achieve 0.6V at 18V input, external feedforward or a two-stage architecture is required.