Monolithic Power Systems Inc. MPQ2143DJ-AEC1-Z

Overview

MPQ2143DJ-AEC1-Z from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, 3A synchronous step-down DC/DC converter with constant-on-time (COT) control, operating from 2.5V–5.5V input and delivering regulated output as low as 0.6V in a TSOT23-8 package. It integrates 80mΩ high-side and 40mΩ low-side MOSFETs, achieves 1.2MHz switching frequency, and draws only 40μA quiescent current - ideal for automotive infotainment power rails and FPGA core voltage regulation.

For engineers reviewing the MPQ2143DJ-AEC1-Z datasheet, MPQ2143DJ-AEC1-Z pinout, MPQ2143DJ-AEC1-Z application, or MPQ2143DJ-AEC1-Z equivalent, key selection criteria include its COT architecture for fast transient response, ±10% power-good window with open-drain PG output, cycle-by-cycle over-current protection, and thermal shutdown at 150°C - all validated for automotive-grade reliability under -40°C to +125°C junction temperature.

Technical Context

The MPQ2143DJ-AEC1-Z employs input-voltage feed-forward COT control to maintain stable 1.2MHz switching across its full 2.5V–5.5V input range while enabling fast load-step response without external compensation. Its internal 0.6V reference and feedback comparator drive a proprietary PWM logic that enforces minimum off-time (50ns) and supports 100% duty-cycle operation in dropout.

It integrates dual power MOSFETs (80mΩ PCH / 40mΩ NCH), a soft-start/soft-stop controller (1.3ms ramp-up, 1ms ramp-down), EN-controlled enable/disable with 2.2V UVLO threshold and 150mV hysteresis, and a dedicated open-drain PG pin with 500kΩ internal pull-up and ±10% trip window referenced to VFB.

Key Specifications

Pinout & Package

MPQ2143DJ-AEC1-Z is housed in a thermally enhanced TSOT23-8 package (JEDEC MO-193BA), with 0.65mm pitch, exposed pad for thermal dissipation, and pin 1 identified by lower-left marking when reading top mark left-to-right.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ2143DJ-AEC1-Z, MPQ2179 offers higher current and lower IQ in identical packaging - making it the direct replacement for new designs - while TPS62864AQRGZTQ1 trades pin compatibility for superior accuracy and frequency, requiring layout revision but enabling tighter regulation in safety-critical analog domains.

Availability

MPQ2143DJ-AEC1-Z is available at Aetrix Electronics and suitable for automotive infotainment, ADAS sensor interface, and telematics control unit applications requiring stable component supply and AEC-Q100 qualification.

Supply support for MPQ2143DJ-AEC1-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 MPQ2143 belongs to MPS's automotive-qualified DC/DC converter product line, engineered specifically for demanding automotive subsystems requiring high efficiency, small form factor, and robust fault protection under wide temperature and voltage ranges.

FAQ

What does "NOT RECOMMENDED FOR NEW DESIGNS" mean for MPQ2143DJ-AEC1-Z?

This designation indicates Monolithic Power Systems has released a functional successor (MPQ2179) with improved specifications and recommends it for all new designs. MPQ2143DJ-AEC1-Z remains fully supported for existing production and legacy program continuity, with no announced obsolescence date or reduced quality assurance.

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

Yes - MPQ2143DJ-AEC1-Z supports 100% duty cycle operation when input voltage drops near the output voltage (dropout condition), enabling uninterrupted regulation down to VIN = VOUT + 0.5V. This behavior is intrinsic to its COT architecture and does not require external circuitry or mode switching.

How does the soft-stop function prevent VIN overshoot during shutdown?

During EN-driven shutdown, MPQ2143DJ-AEC1-Z activates the low-side MOSFET to transfer stored energy from the output capacitor back to the input rail. To avoid VIN exceeding 6V absolute maximum, designers must ensure COUT ≤ (36 × CIN) / (VIN − VOUT)² - e.g., with VIN=5V, VOUT=3.3V, and CIN=20μF, COUT must be <20μF.

Is the PG pin compatible with 1.8V or 3.3V logic interfaces?

Yes - the PG pin is open-drain with internal 500kΩ pull-up to VIN, so its HIGH state follows VIN (2.5V–5.5V). For interfacing with 1.8V/3.3V logic, add an external pull-down resistor to limit voltage or use a level-shifter; the internal MOSFET can sink ≥1mA at 0.4V, ensuring reliable LOW assertion.

What is the minimum recommended output capacitor ESR for stable operation?

The MPQ2143DJ-AEC1-Z is optimized for low-ESR ceramic capacitors and remains stable with ESR as low as 5mΩ. Unlike older voltage-mode controllers, its COT architecture does not rely on ESR for loop compensation - enabling use of high-quality X7R/X5R MLCCs without added series resistance.

Does the 40μA quiescent current apply across the full temperature range?

No - the 40μA specification is typical at TJ = +25°C. Over the full −40°C to +125°C junction range, quiescent current increases to ≤65μA (per datasheet Section 4, "Supply Current (Quiescent)"), remaining well below 100μA even at maximum temperature.

How is thermal performance affected by the TSOT23-8 exposed pad?

The TSOT23-8 package features an exposed thermal pad that must be soldered to a PCB copper pour to achieve θJA = 100°C/W. Without thermal pad connection, θJA degrades to ~200°C/W, reducing max continuous output current from 3A to ~1.8A at TA = 25°C - underscoring the necessity of proper thermal land pattern implementation.