Monolithic Power Systems Inc. MP4470GL-Z

Overview

MP4470GL-Z from Monolithic Power Systems is a fully-integrated, synchronous step-down DC/DC converter delivering 5A continuous output current across a 4.5V–36V input range, featuring internal 40mΩ high-side and 20mΩ low-side MOSFETs, 1% reference voltage accuracy, and programmable soft-start. It enables compact, high-efficiency power conversion in space-constrained industrial and automotive subsystems requiring fast transient response and robust protection.

For engineers reviewing the MP4470GL-Z datasheet, MP4470GL-Z pinout, MP4470GL-Z application, or MP4470GL-Z equivalent, key selection criteria include its 200kHz–1MHz adjustable switching frequency, OVP latch (MP4470 only), thermal shutdown at 175°C, and QFN20 (3×4mm) package with exposed thermal pads for enhanced thermal performance.

Technical Context

The MP4470GL-Z implements a current-mode PWM controller with integrated power switches and proprietary switching-loss-reduction technology to maintain high efficiency across load ranges. Its feedback loop uses a precision 815mV reference voltage with ±1% tolerance and supports output regulation from 0.8V to 0.9×VIN via external resistor divider.

It operates in continuous conduction mode (CCM) under heavy load and automatically transitions to skip mode at light loads to sustain >90% efficiency down to 1mA. Protection includes cycle-by-cycle over-current (6A limit), hiccup-mode short-circuit response, UVLO (4.0V rising threshold), and non-latching thermal shutdown with 45°C hysteresis.

Key Specifications

Pinout & Package

MP4470GL-Z is housed in a thermally enhanced 3mm × 4mm, 20-pin QFN package with five exposed thermal pads (pins 8, 19, 21–23) connected to IN and multiple PGND pads (pins 11–16, 24–25) for low-impedance ground return and PCB heat spreading.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP4470AGL-Z, MP4470GL-Z adds critical OVP latch protection for unattended systems; versus RT7295BGSP, it delivers higher current, superior light-load efficiency via skip mode, and integrated bootstrap management for simplified high-VIN designs.

Availability

MP4470GL-Z is available at Aetrix Electronics and suitable for notebook I/O power, automotive infotainment, and industrial PLC I/O modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP4470GL-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 MP4470 product line targets high-density, high-efficiency DC/DC conversion in space- and thermal-constrained applications such as portable computing, automotive electronics, and industrial automation.

FAQ

What is the difference between MP4470GL-Z and MP4470AGL-Z?

The MP4470GL-Z includes an output over-voltage protection (OVP) latch function that disables the device upon detecting V_FB > 1.25×V_REF (≈1.02V), requiring power cycle recovery. MP4470AGL-Z omits this feature while retaining identical pinout, electrical specs, and all other protections including OCP, UVP, and thermal shutdown.

Can MP4470GL-Z operate with ceramic output capacitors?

Yes, but external ramp compensation (R4/C4) is required for stability with low-ESR ceramic capacitors. The datasheet specifies R4 and C4 values based on switching frequency and output voltage; omitting ramp compensation risks subharmonic oscillation and poor transient response.

What is the minimum input voltage for reliable startup?

The MP4470GL-Z starts switching when input voltage exceeds the UVLO rising threshold of 4.0V (typical), with 880mV hysteresis. Below 3.7V, the device remains disabled; operation below 4.5V is not guaranteed per recommended conditions, though functional behavior may occur down to 4.0V.

How does the bootstrap circuit maintain gate drive at high duty cycles?

The MP4470GL-Z integrates a bootstrap refresh mechanism: when V_BST−V_SW drops below 2.3V, the LS-FET conducts briefly to recharge the BST capacitor using the voltage difference between VIN and V_OUT, enabling stable operation up to 95% duty cycle without external charge-pump circuitry.

Is the SS pin compatible with external voltage ramp control?

No - the SS pin is dedicated to soft-start timing via external capacitor only. It sources a fixed 8.5μA current and cannot accept external voltage injection. For dynamic output voltage sequencing, use EN pin control or external DAC-based feedback injection on the FB node.

What thermal derating applies above +85°C ambient?

With θ_JA = 48°C/W on a 4-layer PCB, maximum continuous power dissipation decreases linearly: at +85°C ambient, PD_MAX = (150°C − 85°C)/48°C/W ≈ 1.35W. Layout enhancements (copper area, thermal vias) can improve actual θ_JA and extend usable current at elevated temperatures.

Does PGOOD assertion require external pull-up?

Yes - PGOOD is an open-drain output and must be pulled up to VCC or another valid logic-high voltage (≤6V) via a resistor (typically 10–100kΩ). Without pull-up, the signal remains floating and cannot drive downstream enable or monitoring logic reliably.