Monolithic Power Systems Inc. MPQ8634BGLE-P

Overview

MPQ8634BGLE-P from Monolithic Power Systems is a fully integrated, high-frequency synchronous buck converter delivering up to 20A output current with adjustable current limit, programmable switching frequency (600/800/1000 kHz), and voltage tracking capability. It operates from 4V–16V input, regulates output from 0.9V to 6V, and features internal COT control for ultrafast transient response in telecom power supplies, server PoL rails, and GPU core voltage regulation.

For engineers reviewing the MPQ8634BGLE-P datasheet, MPQ8634BGLE-P pinout, MPQ8634BGLE-P application, or MPQ8634BGLE-P equivalent, key selection criteria include its QFN-21 (3mm×4mm) package thermal performance (θJB = 8°C/W), differential remote sensing for <±1% load regulation, non-latch OCP with 24A current limit threshold, and PGOOD clamping behavior during VIN failure.

Technical Context

The MPQ8634BGLE-P implements adaptive constant-on-time (COT) control with internal ramp compensation, enabling stable operation with zero-ESR MLCC output capacitors and eliminating external loop compensation. Its dual-mode operation-programmable forced CCM or pulse-skip-maintains high efficiency across 0–20A load range while preserving tight output regulation.

It integrates high-side (8.6 mΩ) and low-side (2.5 mΩ) MOSFETs, supports pre-bias start-up, and provides analog TRK/REF input for precise voltage sequencing. Protection includes latch-off OVP (116% VREF), non-latch UVP (80% VREF), OTP (160°C), and negative inductor current limiting at –10A with 200ns timeout.

Key Specifications

Pinout & Package

MPQ8634BGLE-P is housed in a thermally enhanced QFN-21 (3mm × 4mm, 0.5mm pitch) package with exposed thermal pad (EP) connected to PGND. The package supports high-current routing via wide PCB traces on pins 10/21 (VIN), 11–18 (PGND), and 20 (SW), and requires mandatory decoupling on BST, VCC, and TRK/REF.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with RTQ2132B-QT and TPS546D24RSAR, MPQ8634BGLE-P uniquely balances analog simplicity (no firmware), compact footprint (3mm×4mm), and advanced analog features (tracking, remote sense, pre-bias start-up) for high-reliability embedded power delivery.

Availability

MPQ8634BGLE-P is available at Aetrix Electronics and suitable for telecom base station power supplies, cloud server CPU core rails, and GPU memory interface designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MPQ8634BGLE-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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ8634B product line targets high-density, high-efficiency DC/DC conversion in datacenter, networking, and computing infrastructure, emphasizing thermal performance, transient response, and system-level reliability without digital complexity.

FAQ

What is the minimum recommended input capacitance for MPQ8634BGLE-P at 20A output?

A minimum of 22µF low-ESR ceramic capacitance is required near VIN pins (10 and 21), placed with shortest possible trace length. For optimal ripple suppression and transient response under 20A load steps, a parallel combination of 10µF X7R + 12µF X5R is recommended, with total effective capacitance ≥22µF at 100kHz.

How does the TRK/REF pin function during power-up and tracking modes?

During power-up, TRK/REF sets soft-start time via external capacitor (e.g., 1nF → 1.5ms). In tracking mode, it accepts 0.3–1.4V analog input; the FB pin follows this voltage exactly, overriding soft-start and enabling precise sequencing with master rails. Initial TRK/REF must exceed 900mV for valid startup.

Can MPQ8634BGLE-P operate with only ceramic output capacitors?

Yes - its adaptive COT control with internal ramp compensation ensures stability with zero-ESR ceramic capacitors alone. No electrolytic or tantalum capacitors are required. Recommended output capacitance is ≥330µF total (e.g., ten 33µF X7R 0805s) for 20A load step response.

What is the behavior of PGOOD during input supply failure?

When VIN drops below UVLO threshold (2.4V typ.), PGOOD actively clamps to ~0.7V via internal transistor, regardless of external pull-up voltage. This low-level assertion remains until VIN recovers and soft-start completes, providing unambiguous fault signaling to system controllers.

How is over-current protection configured and what happens during a fault?

OCP is set by resistor RCS from CS to AGND, targeting 1.2V threshold (e.g., 10kΩ → 24A limit). Upon detection, the part disables HS-FET for 31 consecutive cycles before latching off. Recovery requires cycling EN or VCC; no auto-retry occurs to prevent thermal runaway.

Is the QFN-21 (3mm×4mm) package lead-free and RoHS-compliant?

Yes - MPQ8634BGLE-P uses lead-free solder finish and complies with EU RoHS Directive 2011/65/EU and China RoHS II. All materials are halogen-free, and the device carries MPS green status per their Quality Assurance documentation.

Does MPQ8634BGLE-P support forced continuous conduction mode at light loads?

Yes - MODE pin configuration (e.g., 30.1kΩ to AGND) forces CCM operation down to zero load, eliminating audible noise and maintaining constant switching frequency. This is essential for noise-sensitive applications like audio processing or precision ADC power rails.