Monolithic Power Systems Inc. MPQ4491MGRE-AEC1-Z

Overview

MPQ4491MGRE-AEC1-Z from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, monolithic USB charging port power converter integrating a synchronous buck regulator (5V/2.5A), USB current-limit switch (2.75A), BC1.2/Divider/1.2V–1.2V auto-detection, programmable line-drop compensation, and selectable switching frequency (150/250/350 kHz). It operates from 7–36V input and targets automotive cigarette lighter adapters and DCP applications.

For engineers reviewing the MPQ4491MGRE-AEC1-Z datasheet, MPQ4491MGRE-AEC1-Z pinout, MPQ4491MGRE-AEC1-Z application, or MPQ4491MGRE-AEC1-Z equivalent, key selection criteria include its integrated USB DCP identification logic, ±8kV HBM ESD rating on DP/DM/USB pins, QFN-25 (4mm×4mm) package with exposed thermal pad, and automotive-grade thermal shutdown (165°C) with 20°C hysteresis.

Technical Context

The device implements peak-current-mode control with fixed-frequency PWM (150/250/350 kHz selectable via FREQ pin), internal 5V VCC LDO regulator powered from VIN, and dual-path protection: hiccup-mode overcurrent (4A buck limit, 2.75A USB limit) and output overvoltage protection (6.0V trip, 5.75V recovery). Its error amplifier uses internal 1V reference and optimized compensation to minimize external components.

USB auto-detection executes a state machine supporting BC1.2 short mode (DP/DM <160Ω), Divider mode (2.7V on DP/DM), and 1.2V/1.2V mode (1.25V on both lines), dynamically adjusting output voltage (5.05V or 5.25V) and line-drop compensation level. Line drop compensation is set via VDROP pin (GND/float/VCC) to deliver 130–500 mV correction at 2.4A load.

Key Specifications

Pinout & Package

MPQ4491MGRE-AEC1-Z is housed in a thermally enhanced QFN-25 (4mm × 4mm) package with wettable flanks and an exposed thermal pad (Pin 25 = PGND). The package supports high-power dissipation (θJA = 44°C/W) and automated optical inspection (AOI).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB charging port power converter applications.

Compared with MPQ4491MGRE-AEC1-Z, the MPQ4491MGR-AEC1-Z offers better thermal resistance but larger footprint, while the NCP81239MNTXG lacks USB functionality entirely-making MPQ4491MGRE-AEC1-Z the only single-chip AEC-Q100 solution with full DCP support and line-drop compensation.

Availability

MPQ4491MGRE-AEC1-Z is available at Aetrix Electronics and suitable for automotive cigarette lighter adapters, USB dedicated charging ports (DCP), and linear charger power supplies requiring stable component supply, AEC-Q100 qualification, and production-ready lead times.

Supply support for MPQ4491MGRE-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 core expertise in DC/DC converters, LED drivers, and motor drivers.

The MPQ4491M product line delivers integrated USB charging solutions for automotive environments, designed specifically to replace multi-chip DCP implementations with AEC-Q100-compliant, thermally robust, and EMI-optimized single-package power conversion.

FAQ

What is the purpose of the VDROP pin, and how does it affect output voltage accuracy?

The VDROP pin selects line-drop compensation amplitude (130/400/500 mV at 2.4A) to offset voltage loss across PCB traces and cables. When set to VCC, it adds 500 mV to the 5.05V nominal output, ensuring ≥4.75V reaches the USB connector even with 200mΩ total resistance-critical for maintaining USB specification compliance under load.

How does the MPQ4491MGRE-AEC1-Z handle USB device detection in BC1.2 mode?

It implements a hardware state machine that applies 0.8V to DP and measures DM current to detect short (<160Ω); if detected, it enters BC1.2 short mode, raises output to 5.25V, and halves line-drop compensation to maximize current delivery-no external processor or firmware is required for full BC1.2 compliance.

Can the MPQ4491MGRE-AEC1-Z operate with input voltage below 7V?

No-the absolute minimum operating input is 7V per datasheet specifications. Below this, the UVLO circuit disables the device (rising threshold = 5.7V, falling = 4.7V), and the internal VCC LDO cannot regulate. For 5V-input applications, a different part such as MPQ4420A is required.

What is the thermal performance difference between QFN-25 and QFN-26 packages?

Both packages have identical θJA (44°C/W) and θJC (9°C/W) values per JEDEC JESD51-7 testing on 4-layer boards. The QFN-25 achieves equivalent thermal performance in a smaller footprint due to optimized thermal pad layout and pin placement-making it ideal for space-constrained automotive modules.

Does the hiccup-mode overcurrent protection reset automatically after fault removal?

Yes-after the overcurrent condition ends, the device exits hiccup mode within one full cycle (3ms ON + 8.5s OFF), then resumes normal PWM operation. This behavior is confirmed in the datasheet's "Buck Over-Current Protection" section and applies identically to both buck and USB switch current limits.

Is the FREQ pin compatible with standard logic voltage levels?

Yes-FREQ interprets logic HIGH as >VCC – 0.4V (≥4.6V at VCC=5V), logic LOW as <0.4V, and floating as mid-level (2.5V). It is electrically compatible with 3.3V and 5V GPIOs, and no external pull-up/down resistors are needed beyond the internal 1MΩ EN pull-down.

How does the device manage USB output discharge during shutdown?

Upon EN deactivation or VIN UVLO, an internal 70Ω discharge path activates between USB and PGND, discharging the output capacitor in <10ms. This prevents backfeeding and ensures safe hot-plug removal-verified in the "USB Output Discharge" section of the datasheet.