Monolithic Power Systems Inc. MP2148GQD-33-Z

Overview

MP2148GQD-33-Z from Monolithic Power Systems is a fixed-output 3.3V, 1A synchronous step-down DC/DC converter in a 1.0mm × 1.5mm QFN-6 package. It operates from 2.3V–5.5V input, delivers 11μA quiescent current, uses Constant-On-Time control for fast transient response, and integrates 120mΩ P-FET and 80mΩ N-FET switches - ideal for powering low-voltage I/O rails in portable devices.

For engineers reviewing the MP2148GQD-33-Z datasheet, MP2148GQD-33-Z pinout, MP2148GQD-33-Z application, or MP2148GQD-33-Z equivalent, key selection criteria include its fixed 3.3V ±1% output accuracy over –40°C to +125°C, integrated power-good indicator with 70μs delay, 2.2MHz switching frequency, and ultra-low IQ operation enabling battery-powered wearable systems to achieve multi-week standby life.

Technical Context

The MP2148GQD-33-Z implements Constant-On-Time (COT) control with input-voltage feed-forward to maintain stable 2.2MHz switching across its 2.3V–5.5V input range. Its internal architecture integrates high-side and low-side MOSFETs with 120mΩ/80mΩ R_DS(on), enabling up to 1A continuous output while supporting 100% duty cycle for near-dropout operation.

It features dedicated power-good (PG) open-drain output with 85%–90% voltage window detection, 70μs delay, and 400mV sink capability under 1mA load. Fault protection includes cycle-by-cycle current limiting (2.4A peak), thermal shutdown at 160°C with 30°C hysteresis, and hiccup-mode short-circuit recovery.

Key Specifications

Pinout & Package

MP2148GQD-33-Z is housed in an ultra-compact QFN-6 package (1.0mm × 1.5mm, 0.5mm pitch) with exposed thermal pad for enhanced heat dissipation in space-constrained layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output buck converter applications.

Compared with TPS62231DRYR and ADP2303ARDZ-3.3-R7, MP2148GQD-33-Z uniquely combines ultra-small QFN-6 packaging, 11μA I_Q, and integrated PG in a single 3.3V 1A solution - making it optimal for miniaturized, long-life battery systems where every μA and mm² matters.

Availability

MP2148GQD-33-Z is available at Aetrix Electronics and suitable for wireless sensor nodes, wearable health monitors, and industrial handheld terminals requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for MP2148GQD-33-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 core expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MP2148 product line targets ultra-compact, ultra-low-power DC/DC regulation for portable and battery-operated electronics - emphasizing minimal external components, sub-1mm profile, and nanoscale quiescent current without sacrificing robustness.

FAQ

What is the purpose of the PG pin on MP2148GQD-33-Z?

The PG (Power Good) pin is an open-drain output that signals valid 3.3V regulation. When VOUT is within 85–90% of nominal (2.805–2.97V), PG pulls high via external pull-up; outside this window, it sinks to ground. Delay is 70μs, and sink capability is rated at ≤400mV under 1mA load - enabling precise system power sequencing.

Does MP2148GQD-33-Z require external feedback resistors?

No. MP2148GQD-33-Z is a fixed-output variant with internal resistor divider set to 3.3V. Unlike the adjustable MP2148GQD, it does not use the FB pin for regulation - instead repurposing Pin 1 as the PG output. External resistors are unnecessary and must not be connected to Pin 1.

Can MP2148GQD-33-Z operate with input voltage below 3.3V?

Yes. It operates from 2.3V to 5.5V input, supporting single-cell Li-ion (3.0–4.2V), LiFePO₄ (2.5–3.65V), and even partially discharged alkaline cells. At VIN = 2.5V, it sustains 3.3V output using 100% duty cycle - critical for brown-out resilience in battery systems.

How does the output discharge function work during shutdown?

When EN is pulled low, MP2148GQD-33-Z activates an internal 1kΩ discharge path between OUT and GND. This safely bleeds stored charge from the output capacitor, preventing floating voltages that could disrupt downstream logic or violate reset timing requirements during power cycling.

Is thermal pad connection mandatory for MP2148GQD-33-Z?

Yes. The exposed thermal pad (EPAD) must be soldered to a solid copper pour tied to GND. It serves as both primary thermal conduction path and critical GND return for high-frequency switch currents. Omitting EPAD connection risks thermal shutdown above 300mW load and degrades EMI performance.

What inductor value is recommended for MP2148GQD-33-Z at 1A load?

A 1.0μH shielded power inductor with ≤15mΩ DCR is recommended - such as Würth 74438322010 or Coilcraft XAL5030-102ME. This value balances ripple current (~30% of 1A), size, and efficiency across 2.3V–5.5V input; values from 0.47μH to 1.5μH are acceptable depending on EMI and transient requirements.

Does MP2148GQD-33-Z support forced PWM or automatic PFM/PWM mode switching?

It uses Advanced Asynchronous Modulation (AAM), a proprietary light-load mode that dynamically transitions between CCM and DCM based on load. There is no user-selectable forced PWM mode; AAM inherently minimizes switching losses at light loads while preserving fast transient response - eliminating need for external mode control.