Monolithic Power Systems Inc. MP2228GJ-P

Overview

MP2228GJ-P from Monolithic Power Systems is a synchronous step-down DC/DC converter with integrated 100mΩ high-side and 40mΩ low-side MOSFETs, delivering up to 2A continuous output current across a 6V–16V input range, fixed 800kHz switching frequency, and adjustable output voltage down to 0.8V - deployed in notebook I/O power, flat-panel TV logic rails, and distributed point-of-load systems.

For engineers reviewing the MP2228GJ-P datasheet, MP2228GJ-P pinout, MP2228GJ-P application, or MP2228GJ-P equivalent, this page delivers verified functional identity, validated TSOT-23-8 pin mapping, confirmed thermal shutdown (150°C) and hiccup-mode OCP behavior, and real-world design constraints including BST capacitor requirements and AAM-programmable light-load mode transition.

Technical Context

The MP2228GJ-P operates in fixed-frequency peak-current-mode control with internal 0.807V reference and optimized compensation network, enabling stable regulation without external loop components. Its current-mode architecture delivers fast transient response to load steps up to 2A while maintaining <±1% line and load regulation over full input and temperature range.

It integrates a 5V internal LDO (VCC) powered from VIN, bootstrap charging circuitry for high-side gate drive, and dual protection schemes: cycle-by-cycle over-current limit (4.5A typ.) plus thermal shutdown with 20°C hysteresis. The AAM pin enables programmable asynchronous modulation to balance light-load efficiency against ripple and stability.

Key Specifications

Pinout & Package

MP2228GJ-P is housed in an 8-pin TSOT-23 package (3.0mm × 3.0mm × 0.9mm), optimized for high-density PCB layouts with exposed thermal pad (pin 4 GND) and tight pitch (0.65mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2228GJ-P, MP2238GJ-Z offers higher current headroom at minor efficiency cost, while RT7272BGJ8F trades pin compatibility and AAM control for greater output capacity - making MP2228GJ-P optimal for cost-sensitive, space-constrained 2A designs requiring programmable light-load behavior.

Availability

MP2228GJ-P is available at Aetrix Electronics and suitable for notebook I/O power, digital set-top box SoC rails, and flat-panel monitor logic supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP2228GJ-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 MP2228 belongs to MPS's high-frequency synchronous buck converter product line, engineered for compact, efficient point-of-load regulation in portable and space-constrained consumer electronics.

FAQ

What is the minimum output voltage achievable with MP2228GJ-P?

The MP2228GJ-P supports output voltages down to 0.8V, set by the internal 0.807V reference voltage and external resistor divider. At 0.8V output, the feedback resistor network must be carefully laid out to minimize noise injection, and the T-type configuration is recommended per the datasheet for improved stability and accuracy.

Does MP2228GJ-P require an external bootstrap diode?

An external bootstrap diode (e.g., 1N4148) is optional and recommended only when duty cycle exceeds 65% - such as in 12V-to-5V or 16V-to-5V configurations - to improve high-side gate drive efficiency and reduce BST capacitor stress. For 12V-to-3.3V (D≈28%), the internal bootstrap circuit suffices.

How is soft-start time calculated for MP2228GJ-P?

Soft-start time is determined by t_SS = (0.8V × C_SS) / 11μA, where C_SS is the capacitor value in farads. For example, a 10nF capacitor yields ~0.73ms ramp time. This linear voltage ramp controls the COMP node to limit inrush current and prevent output overshoot during power-up.

What is the purpose of the AAM pin, and how is it configured?

The AAM pin selects between asynchronous modulation (light-load efficiency) and forced continuous conduction mode (CCM). It is typically driven by a resistor divider from VCC (4.9V) to GND; a 0.5V AAM voltage enables DCM below ~200mA load, while VCC forces CCM regardless of load - balancing efficiency, ripple, and transient response.

Can MP2228GJ-P operate with input voltage below 6V?

No - the absolute minimum operating input voltage is 6V, enforced by internal UVLO with 5.3V rising threshold and 1.1V hysteresis. Operation below 6V will cause the device to shut down; for sub-6V inputs, consider the MP2122 (4.5V–16V range) or MP2143 (2.5V–6V range) as alternatives.

What thermal considerations apply to the TSOT-23-8 package?

The TSOT-23-8 package has θ_JA = 100°C/W on a 4-layer JEDEC PCB. At 2A output with 12V_IN/3.3V_OUT, power dissipation is ~0.5W, resulting in ~50°C junction rise above ambient. To stay within 125°C max TJ, ambient must remain ≤75°C - requiring adequate copper area and ≥4 thermal vias under pin 4 (GND).

Is MP2228GJ-P pin-compatible with other MPS buck converters?

MP2228GJ-P shares the same 8-pin TSOT-23 footprint and pinout with MP2238GJ and MP2248GJ, enabling drop-in replacement for higher-current variants. However, it is not compatible with MP1584 (different pinout) or MP2315 (7-pin SOIC), as pin functions and internal architecture differ significantly.