Monolithic Power Systems Inc. MPQ4462DQ-LF-Z

Overview

MPQ4462DQ-LF-Z from Monolithic Power Systems is a 3.5A, 4MHz, 36V AEC-Q100 Grade 1 qualified synchronous step-down converter with integrated 150mΩ high-side MOSFET, 120µA quiescent current, and programmable switching frequency up to 4MHz - deployed in automotive infotainment power rails and ADAS camera modules.

For engineers reviewing the MPQ4462DQ-LF-Z datasheet, MPQ4462DQ-LF-Z pinout, MPQ4462DQ-LF-Z application, or MPQ4462DQ-LF-Z equivalent, key selection criteria include its 3.8V–36V input range, internal soft-start, ceramic-capacitor stability, AEC-Q100 qualification, and QFN10 (3mm×3mm) thermal performance with exposed pad grounding.

Technical Context

The MPQ4462DQ-LF-Z implements current-mode control with an internal error amplifier (200V/V gain, 60µA/V transconductance), programmable oscillator (set via external resistor to 0.2–4MHz), and cycle-by-cycle peak-current limiting without external sense resistors. Its bootstrap driver supports floating gate drive for the integrated high-side MOSFET, with dedicated UVLO (2.2V rising) and charge path from VIN to BST during SW low periods.

It features frequency foldback at light load to reduce switching losses, minimum ON/OFF times of 80ns/100ns, thermal shutdown at 150°C with 15°C hysteresis, and EN pin logic-level enable with 1.5V rising / 1.2V falling thresholds. The FB pin regulates output from 0.8V to 30V using a precision 0.792V reference (±1.5% over temperature).

Key Specifications

Pinout & Package

MPQ4462DQ-LF-Z is housed in a thermally enhanced 3mm×3mm QFN10 package with exposed thermal pad (pin 10), optimized for automotive PCBs requiring high power density and low thermal resistance (θ_JA = 50°C/W, θ_JC = 12°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 MPQ4462DN-LF-Z, the MPQ4462DQ-LF-Z delivers superior thermal performance and higher current capability in a smaller footprint; versus LM61480-Q1, it offers full integration, simpler layout, and guaranteed ceramic-capacitor stability - making it optimal for space-constrained, high-reliability automotive designs.

Availability

MPQ4462DQ-LF-Z is available at Aetrix Electronics and suitable for automotive infotainment systems, ADAS camera modules, and industrial telematics gateways requiring stable component supply with AEC-Q100 traceability and long-term lifecycle support.

Supply support for MPQ4462DQ-LF-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 MPQ4462 belongs to MPS's automotive-grade DC-DC converter product line, engineered specifically for harsh-environment applications demanding AEC-Q100 qualification, wide input range, and high switching frequency - targeting next-generation vehicle electrification and ADAS subsystems.

FAQ

What is the maximum recommended input voltage for reliable 4MHz operation?

The MPQ4462DQ-LF-Z supports 4MHz switching only when input voltage is ≤12V. At higher VIN (e.g., 24V), maximum stable frequency drops to 2MHz per Figure 2 in the datasheet; exceeding this risks pulse skipping, reduced efficiency, and insufficient BST capacitor recharge time.

Does MPQ4462DQ-LF-Z require an external bootstrap diode?

An external bootstrap diode (e.g., BAT54) is recommended when VIN ≤5V, duty cycle >65%, or during no-load/light-load operation where VIN–VOUT <3V - to ensure adequate BST voltage for high-side MOSFET gate drive and prevent dropout.

How is output voltage accuracy affected across temperature and load?

Output voltage accuracy is dominated by the 0.792V feedback reference, specified at ±1.5% over –40°C to +125°C. Combined with resistor divider tolerance, typical total VOUT error remains within ±2.5% across full load and temperature range - verified in production test data per Rev. 1.12 datasheet.

Can MPQ4462DQ-LF-Z operate with 100% duty cycle?

No - the MPQ4462DQ-LF-Z has a minimum off-time of 100ns and cannot sustain 100% duty cycle. It requires at least one switching cycle per period to recharge the BST capacitor; for near-100% operation, external bootstrap diode and careful layout are mandatory to maintain gate drive.

What is the purpose of the FREQ pin resistor value table?

The FREQ pin resistor table maps standard resistor values (e.g., 18kΩ → 4MHz) to precise oscillator frequencies. This enables EMI optimization (e.g., setting 3.3MHz to avoid sensitive bands) and efficiency tuning - frequency scaling reduces gate-drive loss at light loads while maintaining regulation.

Is the exposed thermal pad electrically connected internally?

Yes - the exposed pad (pin 10) is internally connected to GND and must be soldered to a PCB ground plane with ≥9 thermal vias (15mil barrel, 40mil pitch) to achieve rated 2.5W power dissipation and meet θ_JA = 50°C/W specification.

How does frequency foldback improve light-load efficiency?

Frequency foldback reduces switching frequency proportionally to load current - lowering both switching losses (proportional to f_SW) and gate-drive losses (proportional to f_SW × Q_g). At 10mA load, frequency drops to ~200kHz, increasing efficiency from 65% to >85% compared to fixed-frequency operation.