Monolithic Power Systems Inc. MP2148GQD-15-Z

Overview

MP2148GQD-15-Z from Monolithic Power Systems is a fixed-output 1.5V, 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, features constant-on-time control for fast transient response, and integrates 120mΩ/80mΩ internal PMOS/NMOS power switches. It is used in low-power wearable devices requiring stable, ultra-compact voltage regulation.

For engineers reviewing the MP2148GQD-15-Z datasheet, MP2148GQD-15-Z pinout, MP2148GQD-15-Z application, or MP2148GQD-15-Z equivalent, key selection criteria include fixed 1.5V output accuracy (±1%), hiccup-mode short-circuit protection, integrated output discharge, 2.2MHz switching frequency, and thermal shutdown at 160°C - all critical for battery-powered I/O rail design.

Technical Context

The MP2148GQD-15-Z uses 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 power stage integrates complementary 120mΩ PMOS and 80mΩ NMOS switches, enabling 1A continuous output with minimal external components.

It implements sleep mode and Advanced Asynchronous Modulation (AAM) with zero-current detection (ZCD) to sustain high efficiency at light loads. The fixed 1.5V output version includes an open-drain Power Good (PG) indicator with ±5% window and 70μs delay, activated only when VOUT remains within 85–90% of nominal.

Key Specifications

Pinout & Package

MP2148GQD-15-Z is housed in a thermally enhanced QFN-6 (1.0mm × 1.5mm) package with exposed thermal pad. Pin 1 is marked by a dot or notch; the package is RoHS-compliant, halogen-free, and lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS62231DRYR and ADP2119ACPZ-R7, MP2148GQD-15-Z uniquely combines 1A capability, 11μA IQ, fixed 1.5V accuracy, and 1.0×1.5mm footprint - making it optimal for miniaturized, battery-sensitive 1.5V rail generation where size, efficiency, and integration are co-prioritized.

Availability

MP2148GQD-15-Z is available at Aetrix Electronics and suitable for wireless earbud charging cases, smart watch core rails, and fitness tracker sensor hubs requiring stable component supply, long-lifecycle support, and consistent tape-and-reel delivery for SMT production.

Supply support for MP2148GQD-15-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 MP2148 product line targets ultra-compact, low-IQ DC/DC conversion for portable and wearable electronics, emphasizing minimal external component count, thermal efficiency in tiny packages, and robust protection for battery-critical systems.

FAQ

What is the purpose of the PG pin on MP2148GQD-15-Z?

The PG (Power Good) pin is an open-drain output that signals when the 1.5V output is within ±5% of regulation (1.425V–1.575V). It requires an external pull-up resistor (100kΩ–500kΩ) to a voltage ≤VIN. When active, it pulls high; during undervoltage or startup, it sinks current to ground - enabling precise system reset sequencing.

Can MP2148GQD-15-Z operate with input voltage equal to output voltage?

Yes. MP2148GQD-15-Z supports 100% duty-cycle operation, maintaining regulation even when VIN = VOUT = 1.5V. This is essential for sustaining function as Li-ion batteries discharge below 3.0V, ensuring uninterrupted power to downstream 1.5V logic during brown-out conditions.

How does the output discharge feature work and when is it active?

When EN is pulled low, an internal 1kΩ discharge MOSFET connects OUT to GND, actively discharging the output capacitor. This clears residual voltage within ~1ms, preventing back-powering of upstream circuitry or unintended wake-up of connected peripherals during shutdown.

Is an external feedback resistor divider required for MP2148GQD-15-Z?

No. MP2148GQD-15-Z is a fixed-output variant; the 1.5V regulation is implemented internally. Unlike the adjustable MP2148GQD, it has no FB pin functionality - pin 1 serves exclusively as PG. No external resistors are needed for voltage setting.

What thermal derating applies above 25°C ambient?

With θJA = 220°C/W, maximum continuous power dissipation drops linearly: PD(MAX) = (150°C − TA)/220. At 85°C ambient, PD(MAX) = 0.30W. Derating begins immediately above 25°C; full 1A output requires careful PCB copper area and thermal pad soldering to maintain TJ ≤ 125°C.

Does MP2148GQD-15-Z require special layout considerations for EMI reduction?

Yes. Place the input capacitor (≥10μF X5R ceramic) directly between VIN (pin 3) and GND (pin 2); keep SW (pin 4) trace short and远离 feedback paths; avoid routing PG or EN near SW; and connect the exposed thermal pad to a solid internal ground plane using ≥4 thermal vias for optimal thermal and EMI performance.

What protection features are built into MP2148GQD-15-Z?

It integrates cycle-by-cycle current limiting (2.4A PMOS peak), hiccup-mode short-circuit recovery, thermal shutdown (160°C), under-voltage lockout (2.25V rising threshold), and output discharge. No external components are needed to enable any of these protections.