Monolithic Power Systems Inc. MPQ4470GL-Z

Overview

MPQ4470GL-Z from Monolithic Power Systems is a high-efficiency, synchronous step-down DC/DC converter delivering 5A continuous output current across a 4.5V–36V input range. It integrates 40mΩ high-side and 20mΩ low-side MOSFETs, features latch-off over-voltage protection (OVP), and operates at 100kHz–1MHz switching frequency in a thermally enhanced 3mm×4mm QFN-20 package. It is AEC-Q100 Grade 1 qualified and used in automotive power rails requiring fast transient response and robust fault protection.

For engineers reviewing the MPQ4470GL-Z datasheet, MPQ4470GL-Z pinout, MPQ4470GL-Z application, or MPQ4470GL-Z equivalent, this page provides verified technical context, validated pin functions, confirmed protection behavior (including OVP latch), real-world efficiency curves, and direct alternatives with documented functional differences - all grounded in Monolithic Power's Rev. 1.12 datasheet and official package documentation.

Technical Context

The MPQ4470GL-Z employs fixed-frequency, current-mode PWM control with feed-forward input voltage compensation to maintain stable switching frequency across wide VIN ranges. Its proprietary dead-time management prevents shoot-through between integrated 40mΩ/20mΩ MOSFETs, while internal bootstrap regulation enables low-dropout operation down to VOUT ≈ 0.8V.

It implements cycle-by-cycle over-current protection with 100μs hiccup timer, non-latching thermal shutdown at 175°C (45°C hysteresis), and UVLO with 4.0V rising / 3.1V falling thresholds. The OVP latch function triggers at 1.25×VREF (≈1.01V) and forces hard shutdown until power cycle - a key differentiator from MPQ4470AGL-Z.

Key Specifications

Pinout & Package

MPQ4470GL-Z is housed in a thermally optimized 3mm×4mm, 20-pin QFN package with exposed thermal pads (pins 8, 19, 21, 22, 23 for IN; pins 9, 10, 17, 18, 24, 25 for SW; pins 11–16 for PGND). The package supports high-current routing via multiple vias and wide copper traces.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ4470AGL-Z, MPQ4470GL-Z adds critical fail-safe OVP latch for automotive and telecom systems exposed to uncontrolled input surges; compared with LM61480RQR, it offers drop-in replacement compatibility, smaller footprint, and integrated latch-off - at the cost of lower peak current rating.

Availability

MPQ4470GL-Z is available at Aetrix Electronics and suitable for automotive infotainment, industrial PLC I/O modules, and optical transceiver bias supplies requiring stable component supply, AEC-Q100 compliance, and production-ready lead times.

Supply support for MPQ4470GL-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 conversion, motor drivers, and LED lighting controllers.

The MPQ4470 series belongs to MPS's automotive-grade synchronous buck converter product line, designed specifically for demanding 12V/24V systems requiring high efficiency, fast transient response, and robust fault protection in harsh environments.

FAQ

What is the difference between MPQ4470GL-Z and MPQ4470AGL-Z?

The MPQ4470GL-Z includes latch-off over-voltage protection (OVP), which disables the device and holds shutdown until power cycle when output exceeds 1.25×VREF. MPQ4470AGL-Z omits this feature but is otherwise pin- and function-compatible, sharing identical electrical specs, package, and protection suite except OVP latch.

Does MPQ4470GL-Z require an external bootstrap capacitor?

Yes - a 0.1µF to 1µF ceramic capacitor must be placed between BST and SW pins to supply gate drive voltage for the integrated high-side MOSFET. This capacitor is charged during low-side conduction and must be located within 2mm of the BST/SW pins with short, wide traces to ensure reliable startup and dropout operation.

Can MPQ4470GL-Z operate with ceramic output capacitors without external ramp compensation?

No - for ceramic output capacitors (low ESR), external ramp compensation (R4/C4) is required to stabilize the feedback loop in PWM mode. Without it, VFB slope instability causes jitter and potential oscillation. POSCAP or higher-ESR capacitors may omit ramp components but sacrifice transient response and size efficiency.

What is the minimum recommended soft-start capacitor value?

The minimum soft-start capacitor is 4.7nF when output capacitance exceeds 330µF, to prevent current-limit triggering during ramp-up. For smaller output caps, CSS can be reduced - e.g., 2.2nF yields ~2ms ramp time with 8.5µA internal charge current and 0.815V reference.

How does the PGOOD pin behave during startup and fault conditions?

PGOOD is open-drain and pulled LOW until VFB reaches 90%×VREF (≈0.733V), then goes HIGH after a 700μs delay. It falls LOW again when VFB drops below 85%×VREF (≈0.693V). During OVP latch or thermal shutdown, PGOOD remains LOW and does not assert HIGH until full recovery and re-ramp.

Is MPQ4470GL-Z compatible with 48V input systems?

No - its absolute maximum input voltage is 40V, and recommended operating range is 4.5V–36V. For 48V intermediate bus applications, consider MPS's MPQ4363 or MPQ4331 families, which support up to 60V input and include similar protection features.

What thermal resistance values apply to the QFN-20 package?

The MPQ4470GL-Z QFN-20 (3mm×4mm) has θ_JA = 48°C/W and θ_JC = 10°C/W when mounted on a 4-layer JEDEC-standard PCB (JESD51-7). Effective thermal performance depends on exposed pad soldering quality and copper area - ≥200mm² of 2oz copper with 6+ thermal vias is recommended for 5A operation.