Monolithic Power Systems Inc. MPQ4423HGQ-P

Overview

MPQ4423HGQ-P from Monolithic Power Systems is a high-efficiency, AEC-Q100 Grade 1 qualified synchronous step-down DC/DC converter delivering 3A continuous output current across a 4V–36V input range. It integrates 85mΩ/55mΩ high-side/low-side MOSFETs, operates at 410kHz (synchronizable to 200kHz–2.2MHz), and supports automotive cold-crank with >95% duty cycle capability. Used in vehicle infotainment power rails and ADAS camera modules.

For engineers reviewing the MPQ4423HGQ-P datasheet, MPQ4423HGQ-P pinout, MPQ4423HGQ-P application, or MPQ4423HGQ-P equivalent, key selection criteria include its wettable flank QFN-8 package for automated optical inspection, integrated power-good signaling, thermal shutdown with 30°C hysteresis, and programmable UVLO via EN pin divider.

Technical Context

The MPQ4423HGQ-P employs peak-current-mode control with internal compensation, enabling stable regulation across wide VIN and load transients. Its bootstrap driver supports high-duty-cycle operation up to 95%, critical for automotive 3.3V/5V rails during cold-crank (VIN down to 4V).

It features dual-stage protection: cycle-by-cycle over-current limit (3.2–5.7A) followed by hiccup mode upon sustained FB voltage drop below 84% of 0.792V reference, plus thermal shutdown at 170°C with 30°C hysteresis. The PG pin provides open-drain status with 90μs delay and 6% hysteresis relative to VFB.

Key Specifications

Pinout & Package

MPQ4423HGQ-P is housed in a space-saving, AEC-Q100-compliant QFN-8 (3mm × 3mm) package with wettable flanks for solder joint inspection. Thermal pad on underside requires direct connection to PCB ground plane for optimal heat dissipation (θJC = 13°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM61480QRNTRQ1 and TPS543320RHLR, MPQ4423HGQ-P uniquely balances AEC-Q100 Grade 1 qualification, wettable flank inspection readiness, and true cold-crank operation (4V–36V, >95% duty) in a 3A-class footprint - making it the preferred choice for cost-sensitive, safety-aware automotive subsystems.

Availability

MPQ4423HGQ-P is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and industrial motor drive control requiring stable component supply with full AEC-Q100 traceability and long-term lifecycle support.

Supply support for MPQ4423HGQ-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 MPQ4423H product line targets automotive-grade DC/DC conversion, emphasizing AEC-Q100 reliability, cold-crank resilience, and compact integration for next-generation vehicle electronics.

FAQ

What is the minimum input voltage required for MPQ4423HGQ-P to start switching?

The device initiates switching when both VIN exceeds 3.5V (UVLO rising threshold) and EN is pulled above 1.4V. Below 3.5V, the internal regulator cannot sustain bias, preventing startup even if EN is asserted. This ensures reliable cold-crank operation down to 4V nominal input.

Can MPQ4423HGQ-P operate with an output voltage lower than 0.8V?

No - the internal reference is fixed at 0.792V ±12mV, and the feedback amplifier is designed for regulation ≥0.8V. Attempting sub-0.8V outputs violates the error amplifier's common-mode input range and results in unregulated behavior or instability.

Is the BST capacitor mandatory, and what value is recommended?

Yes - the BST capacitor is essential for high-side gate drive. A 0.1µF to 1µF X7R ceramic capacitor rated ≥16V must be placed between BST and SW pins. A 20Ω resistor in series is strongly recommended to dampen SW node ringing and improve EMI performance.

How does the hiccup mode function during output short-circuit?

When FB drops below 84% of the reference (≈0.669V), the IC enters hiccup mode: it disables switching for ~10ms, then attempts restart. This limits average short-circuit current to ~1.2A and die temperature rise, preventing thermal runaway while allowing automatic recovery once the fault clears.

Does MPQ4423HGQ-P support forced PWM mode, or is it always in auto PSM?

It operates exclusively in automatic power-save mode (PSM) at light loads - no external pin or register controls forced PWM. Below ~200mA, it skips cycles to maintain efficiency; above that, it transitions seamlessly to fixed-frequency current-mode operation without audible noise or regulation degradation.

What is the purpose of the T-type feedback network shown in the datasheet?

The T-network (R1, R2, RT) improves loop stability for low-output-voltage designs (<3.3V) by adjusting phase margin. RT adds a zero to counteract the ESR zero of ceramic output capacitors, enabling stable operation with high-C, low-ESR MLCCs without external compensation components.

How is thermal performance affected by omitting the thermal pad connection?

Omitting the thermal pad connection increases θJA from 55°C/W to >100°C/W, causing junction temperature to exceed 150°C at just 1.5A load in still air. This triggers thermal shutdown and risks permanent damage - the exposed pad must be soldered to a solid ground plane with ≥4 thermal vias.