Monolithic Power Systems Inc. MPQ9843GLE-5-AEC1-P

Overview

MPQ9843GLE-5-AEC1-P from Monolithic Power Systems is a 36V, 3A, AEC-Q100 Grade-1 qualified synchronous step-down converter with fixed 5V output, 14μA no-load quiescent current, 350kHz–2.5MHz programmable switching frequency, and integrated 125mΩ/55mΩ MOSFETs. It delivers high efficiency in automotive infotainment power rails and ADAS camera modules under wide input transients (3.3V–36V).

For engineers reviewing the MPQ9843GLE-5-AEC1-P datasheet, MPQ9843GLE-5-AEC1-P pinout, MPQ9843GLE-5-AEC1-P application, or MPQ9843GLE-5-AEC1-P equivalent, key selection criteria include AEC-Q100 Grade-1 qualification, wettable flank QFN-16 package for automated optical inspection, 80ns minimum on-time for high-duty-cycle operation, and PG signal with ±5% threshold accuracy over –40°C to +125°C.

Technical Context

The MPQ9843GLE-5-AEC1-P uses peak-current-mode control with internal error amplifier and PLL-based oscillator, enabling fast transient response and stable loop compensation without external compensation components. Its selectable forced CCM or AAM mode allows dynamic efficiency optimization across load ranges - CCM ensures constant frequency during EMI-sensitive operation, while AAM reduces switching losses at light loads.

It integrates bootstrap refresh logic, hiccup-mode over-current protection, thermal shutdown with 20°C hysteresis, and precision 0.8V feedback reference (±1.5% over temperature). The BIAS pin supports external 5–18V bias supply to reduce power dissipation and improve full-load efficiency by bypassing the internal VCC regulator.

Key Specifications

Pinout & Package

MPQ9843GLE-5-AEC1-P is housed in a wettable flank QFN-16 (3mm × 4mm) package with exposed thermal pad, optimized for automotive reflow inspection and thermal performance (θJA = 48°C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4420AGL-AEC1-P and TPS543B20RTWR, MPQ9843GLE-5-AEC1-P uniquely combines AEC-Q100 Grade-1, 36V input rating, fixed 5V output with PG, and wettable flank packaging - making it the only drop-in solution for safety-critical 5V power in modern automotive ECUs.

Availability

MPQ9843GLE-5-AEC1-P is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and telematics control units requiring stable component supply with full AEC-Q100 traceability and PPAP support.

Supply support for MPQ9843GLE-5-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 core expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MPQ9843 belongs to MPS's automotive-grade power management portfolio, designed specifically for demanding vehicular environments requiring AEC-Q100 qualification, extended temperature operation, and robust EMI performance.

FAQ

What is the purpose of the BIAS pin, and when should it be used?

The BIAS pin accepts an external 5–18V supply to power the internal control circuitry, bypassing the VIN-to-VCC LDO. This reduces power dissipation and improves efficiency-especially above 1A load-by eliminating the dropout loss of the internal regulator. Use BIAS when optimizing full-load thermal performance or when VIN exceeds 18V.

How does the PHASE pin affect synchronization behavior?

The PHASE pin selects whether the internal oscillator locks in-phase (PHASE = HIGH) or 180° out-of-phase (PHASE = LOW) with the external SYNC clock. This enables interleaving with other converters to reduce input/output ripple. If unused, tie PHASE to GND to avoid floating node noise coupling.

Can the MPQ9843GLE-5-AEC1-P operate without an external soft-start capacitor?

Yes. Leaving the SS pin floating activates the internal 0.7ms soft-start timer. An external capacitor is optional and used only when longer soft-start times (e.g., >5ms) are needed to coordinate with other power rails or limit inrush into large output capacitance banks.

What is the function of the FREQ pin, and how is frequency set?

The FREQ pin sets switching frequency via a resistor to PGND: 180kΩ yields ~475kHz, 82kΩ yields ~1MHz, and 27kΩ yields ~2.5MHz (typical). This resistor determines oscillator current; values outside the 27kΩ–180kΩ range may cause instability or out-of-spec operation.

Is the PG signal actively driven or open-drain, and what pull-up is recommended?

The PG pin is an open-drain N-channel MOSFET output. It requires an external pull-up resistor to a valid logic-high voltage (e.g., 5V or 3.3V). A 100kΩ resistor is typical for low current draw; lower values (e.g., 10kΩ) improve rise time for fast reset assertion but increase static current.

Does the MPQ9843GLE-5-AEC1-P support spread-spectrum frequency modulation?

No. The MPQ9843GLE-5-AEC1-P does not include built-in spread-spectrum modulation. EMI reduction is achieved through selectable CCM/AAM modes, optimized layout guidance, and compatibility with external EMI filters-as validated per CISPR 25 Class 5 in the datasheet application circuit.

What is the maximum allowable thermal pad copper area for the QFN-16 package?

The thermal pad must be connected to a solid PGND plane using ≥4 thermal vias (0.3mm diameter, spaced evenly). While larger copper areas improve θJA, excessive isolation of the thermal pad from surrounding PGND pours degrades heat spreading. Follow MPS EV9843-L-00A reference layout: 6.35cm × 6.35cm, 2oz copper, 4-layer stackup.