Monolithic Power Systems Inc. MPQ8636AGLE-10-Z

Overview

MPQ8636AGLE-10 from Monolithic Power Systems is a fully integrated, synchronous step-down DC/DC converter delivering up to 10A output current from a 4.5V–18V input, featuring Constant-On-Time (COT) control, 0.611V–13V adjustable output, and integrated 19.6mΩ/7.8mΩ MOSFETs in a 3mm×4mm QFN-16 package. It targets high-density power rails in telecom base stations and server VRMs where fast transient response and thermal robustness are critical.

For engineers reviewing the MPQ8636AGLE-10 datasheet, MPQ8636AGLE-10 pinout, MPQ8636AGLE-10 application, or MPQ8636AGLE-10 equivalent, key selection criteria include its adaptive COT architecture for sub-10µs load-step recovery, programmable 200kHz–1MHz switching frequency via external resistor, latch-off OVP at 130% VREF, and pre-bias startup capability for hot-swap systems.

Technical Context

The MPQ8636AGLE-10 implements adaptive Constant-On-Time (COT) control without an external oscillator, deriving ON-time from VIN and a resistor on the FREQ pin to maintain near-constant frequency across input voltage variation. Its dual-MOSFET power stage integrates asymmetric RDS(ON) (HS: 19.6mΩ, LS: 7.8mΩ) optimized for high-side conduction during heavy loads and low-side conduction during light-load CCM operation.

Protection logic includes three-tier current limiting: cycle-by-cycle HS peak limit (13–21.6A), LS valley limit (9.5–12.5A), and LS negative current limit (−6.5 to −4.5A), plus latch-off OVP at 130% VREF and UVP at 50% VREF. The PG pin provides open-drain status with 2.5ms delay and 91%/80% VFB thresholds, while thermal shutdown activates at 150°C with 25°C hysteresis.

Key Specifications

Pinout & Package

MPQ8636AGLE-10 is housed in a thermally enhanced 16-pin QFN package (3mm × 4mm, 0.5mm pitch) with exposed thermal pad. Pin 1 is marked by a dot; pins 9/14 are IN, pins 10/11/12/13 are PGND, and pins 15/16 are SW - all require wide copper pours and multiple vias for thermal and current handling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ8636AGLE-10, MPQ8636DGL-10 offers extended thermal range at identical cost and footprint, while TPS546B24RVFT adds digital control and scalability at the expense of size, complexity, and design effort - making MPQ8636AGLE-10 optimal for analog-controlled, space-constrained 10A rails.

Availability

MPQ8636AGLE-10 is available at Aetrix Electronics and suitable for telecom base stations, server VRMs, and flat-panel display power supplies requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MPQ8636AGLE-10 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 over two decades of expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MPQ8636A product line delivers compact, high-current synchronous buck converters for space-constrained infrastructure equipment, emphasizing thermal efficiency, transient performance, and robust protection in 4.5V–18V input environments.

FAQ

What is the minimum recommended output capacitance for stable operation?

The MPQ8636AGLE-10 requires ≥330µF total output capacitance when using ceramic capacitors with low ESR. If using POSCAPs or polymer capacitors, ≥100µF is sufficient due to their higher ESR providing inherent slope compensation. Layout must minimize trace inductance between SW, PGND, and output caps.

Can the MPQ8636AGLE-10 operate with an input voltage below 4.5V?

No - the absolute minimum operating input voltage is 4.5V per datasheet specifications. Below this, the internal VCC LDO cannot regulate, causing erratic behavior or failure to start. The UVLO threshold is fixed at 4.1V (rising), and no configuration can lower the operational floor.

How is the switching frequency affected by input voltage variation?

Frequency remains nearly constant across input voltage changes due to feed-forward compensation: the FREQ pin connects to IN through a resistor, causing the one-shot ON-time timer to scale with VIN. Measured deviation is <±3% from 4.5V to 18V when RFREQ = 453kΩ.

Does the MPQ8636AGLE-10 support forced continuous conduction mode (FCCM)?

No - it operates exclusively in continuous conduction mode (CCM) under all load conditions. Light-load inductor current goes negative, but the device does not enter discontinuous or pulse-skipping modes. This ensures predictable EMI profile and consistent transient response.

What is the maximum allowable thermal pad copper area on the PCB?

No upper limit exists - maximize the thermal pad copper area using multiple thermal vias (≥8×0.3mm diameter) to inner ground planes. The QFN-16 package's θJA is specified at 46°C/W on a 4-layer JEDEC board; doubling copper area typically improves θJA by 8–12°C/W.

Is the soft-start time adjustable independently of output voltage?

Yes - soft-start time is set solely by the external capacitor on the SS pin and the internal 20µA current source (tSS ≈ CSS × 30.5V/20µA). It is independent of output voltage setting; however, for outputs >5V or large output capacitance (>1000µF), use ≥10nF to avoid current-limit triggering.

What happens during a short-circuit event on the output?

Upon short-circuit, the high-side peak current limit (13–21.6A) triggers immediately, forcing cycle-by-cycle shutdown. The device enters hiccup mode after repeated faults - latching off for ~50ms before retrying - preventing thermal runaway while allowing automatic recovery if fault clears.