Monolithic Power Systems Inc. MPQ2143DJ-AEC1-P

Overview

MPQ2143DJ-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous step-down DC/DC converter delivering up to 3A continuous output current from a 2.5V–5.5V input, with 0.6V minimum output voltage, 1.2MHz switching frequency, and 40μA quiescent current. It integrates 80mΩ high-side and 40mΩ low-side MOSFETs, employs constant-on-time (COT) control for fast transient response, and targets automotive power rails for DSPs, FPGAs, and infotainment subsystems.

For engineers reviewing the MPQ2143DJ-AEC1-P datasheet, MPQ2143DJ-AEC1-P pinout, MPQ2143DJ-AEC1-P application, or MPQ2143DJ-AEC1-P equivalent, key selection criteria include its AEC-Q100 qualification, TSOT23-8 package footprint, COT-based light-load efficiency, ±10% power-good window, and explicit "not recommended for new designs" status requiring migration planning to MPQ2179.

Technical Context

The MPQ2143DJ-AEC1-P implements constant-on-time (COT) control with input-voltage feed-forward to maintain stable 1.2MHz switching across its 2.5V–5.5V input range and supports 100% duty cycle in dropout. Its internal architecture integrates matched high-side (80mΩ) and low-side (40mΩ) MOSFETs, a 0.6V reference with ±1.5% initial tolerance, and a dedicated open-drain PG pin with 500kΩ internal pull-up.

It features cycle-by-cycle over-current protection triggering hiccup-mode recovery at 4.8A (typ), thermal shutdown at 150°C with 30°C hysteresis, soft-start (1.3ms) and soft-stop (1ms) timing, and EN-controlled sequencing with 2.2V UVLO threshold and 150mV hysteresis - all optimized for automotive-grade reliability in space-constrained modules.

Key Specifications

Pinout & Package

MPQ2143DJ-AEC1-P is housed in a thermally enhanced TSOT23-8 package (JEDEC MO-193BA), measuring 2.9mm × 1.6mm × 0.85mm, with exposed pad for improved heat dissipation and 100°C/W junction-to-ambient thermal resistance on a 4-layer PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ2143DJ-AEC1-P, MPQ2179 offers higher input voltage tolerance and output current for next-gen automotive platforms, while MP2143GJ-Z trades qualification for lower unit cost in non-automotive contexts - both require revalidation of thermal performance and PG timing in existing layouts.

Availability

MPQ2143DJ-AEC1-P is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and telematics control units requiring stable component supply amid ongoing industry transition to newer-generation regulators.

Supply support for MPQ2143DJ-AEC1-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 over two decades of leadership in DC/DC conversion, motor drivers, and LED lighting controllers.

The MPQ21xx product line delivers compact, AEC-Q100-qualified buck converters targeting automotive subsystems demanding high efficiency, small footprint, and robust fault protection - designed specifically for infotainment, ADAS, and body electronics.

FAQ

Is MPQ2143DJ-AEC1-P still recommended for new automotive designs?

No - the official datasheet explicitly states "NOT RECOMMENDED FOR NEW DESIGNS, REFER TO MPQ2179". This reflects MPS's end-of-life planning; MPQ2179 offers superior input range (2.7V–18V), higher output current (4A), lower IQ (25μA), and extended temperature grade, making it the designated successor for all new projects.

What is the function of the OUT pin, and how should it be connected?

The OUT pin is the output voltage sense terminal, not a power output. It must be connected directly to the output capacitor's positive terminal, adjacent to the load, to provide accurate remote sensing and improve load regulation. It is distinct from the FB pin, which connects to the resistor divider - using OUT instead of FB for feedback improves transient response and reduces output droop under heavy load steps.

How does the soft-stop feature work, and what design precautions are needed?

When disabled via EN, MPQ2143DJ-AEC1-P linearly discharges its internal reference to ramp down VOUT over ~1ms, transferring energy back to VIN. If output capacitance (C2) is large relative to input capacitance (C1), VIN can overshoot its 6V absolute maximum rating. To prevent this, C2 must satisfy C2 < (C1 × (VIN − VOUT)²)/36 - e.g., with C1 = 20μF, VIN = 5V, VOUT = 3.3V, C2 must be <20μF.

Can MPQ2143DJ-AEC1-P operate with 100% duty cycle, and under what conditions?

Yes - it supports 100% duty cycle in dropout mode when VIN ≤ VOUT + voltage drop across the high-side MOSFET. This occurs during low-input conditions (e.g., VIN = 2.8V regulating 2.5V), allowing uninterrupted operation without pulse-skipping or regulation loss - critical for maintaining power to safety-critical MCUs during cold-crank events.

What is the purpose of the separate PGND and AGND pins, and how should they be routed?

PGND carries high di/dt switching currents from VIN, SW, and OUT; AGND serves as quiet reference for FB, EN, and internal comparators. They must be connected at a single low-impedance point near the IC's exposed pad to prevent ground bounce from corrupting feedback accuracy. Splitting or daisy-chaining these grounds introduces noise that degrades regulation and can cause instability or false PG assertions.

Does MPQ2143DJ-AEC1-P require external compensation components?

No - its constant-on-time (COT) control architecture is inherently stable with ceramic output capacitors and requires no external compensation network. The internal loop is optimized for low-ESR ceramics (e.g., 22μF X5R), eliminating the need for type-II or type-III compensation networks common in voltage-mode or current-mode PWM controllers.

What is the significance of the "ACE" top marking on MPQ2143DJ-AEC1-P?

"ACE" is the unique laser-marked identifier on the TSOT23-8 package confirming authenticity and traceability to Monolithic Power Systems' AEC-Q100 Grade 1 qualified production lot. It distinguishes this automotive-grade variant from industrial versions (e.g., MP2143GJ-Z) and verifies compliance with stress testing including HTOL, TC, and UHAST per AEC-Q100 Rev G.