Monolithic Power Systems Inc. MPQ8633B-HGLE-P

Overview

MPQ8633B-HGLE-P from Monolithic Power Systems is a fully integrated, high-frequency synchronous step-down converter delivering up to 20A output current with 0.6V–5.5V adjustable output voltage, 600–1000kHz configurable switching frequency, and differential remote sensing. It operates across 4V–16V input range, features adaptive constant-on-time (COT) control for fast transient response, and supports voltage tracking via TRK/REF pin in telecom power delivery and server POL applications.

For engineers reviewing the MPQ8633B-HGLE-P datasheet, MPQ8633B-HGLE-P pinout, MPQ8633B-HGLE-P application, or MPQ8633B-HGLE-P equivalent, key selection criteria include its non-latch OCP with configurable current limit, PGOOD active-clamp behavior during input failure, pre-bias start-up capability, and QFN-21 (3mm×4mm) thermal performance with θJB = 8°C/W.

Technical Context

The MPQ8633B-HGLE-P implements adaptive COT control with internal ramp compensation, enabling stable operation with zero-ESR MLCC output capacitors across full VIN (4–16V) and VOUT (0.6–5.5V) ranges. Its valley-current sensing architecture enables cycle-by-cycle over-current protection using external RCS resistor and internal 1.2V OCP threshold.

Mode selection is achieved via MODE pin resistor configuration, supporting FCCM or PSM at three discrete frequencies (600/800/1000kHz), while TRK/REF serves dual function: external reference input (0.3–1.4V) for voltage tracking and soft-start timing capacitor node with 1ms minimum ramp.

Key Specifications

Pinout & Package

MPQ8633B-HGLE-P is housed in a thermally enhanced QFN-21 package (3mm × 4mm, 0.5mm pitch) with exposed thermal pad (PGND-connected) and 21 terminals arranged in a single-row perimeter layout. The package supports JEDEC MSL Level 1 handling and achieves θJB = 8°C/W when mounted on 2oz copper with 4 thermal vias.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ8633D-AEC1-P, the MPQ8633B-HGLE-P offers lower cost and optimized thermal performance for commercial infrastructure, while RTQ2132BGQW trades transient speed for simpler loop design-making the MPQ8633B-HGLE-P preferred for high-dV/dt, multi-rail telecom/server applications requiring tracking and fast load steps.

Availability

MPQ8633B-HGLE-P is available at Aetrix Electronics and suitable for telecom power delivery, server point-of-load, and graphics card memory rail applications requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MPQ8633B-HGLE-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 power management ICs, with over 20 years of expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MPQ8633B product line targets high-current, high-efficiency POL converters for datacenter, networking, and consumer electronics, emphasizing thermal efficiency, fast transient response, and system-level integration like voltage tracking and pre-bias start-up.

FAQ

What is the minimum recommended soft-start capacitor value for MPQ8633B-HGLE-P?

The datasheet specifies CSS2 ≥22nF as the minimum ceramic capacitor on TRK/REF for reliable soft-start timing. With CTRK/REF = 22nF, tSS ≈ 1.3ms at 25°C. Lower values risk inconsistent ramp behavior or failure to initiate regulation; X7R/X5R dielectrics are mandatory for temperature stability.

Can MPQ8633B-HGLE-P operate with only external 3.3V bias and no VIN applied?

No. The device requires VIN ≥4V to power internal MOSFETs and bootstrap circuitry. External 3.3V bias on VCC only supplies control logic; it cannot sustain switching operation. Attempting operation with VIN = 0V results in PGOOD clamp at ~0.7V and immediate shutdown.

How does the negative current limit function during light-load PSM operation?

When inductor current reaches –18A, the LS-FET turns off for 200ns to prevent reverse conduction. This limits negative current without triggering hiccup mode, preserving output voltage stability during abrupt load removal in PSM-critical for memory rail hold-up time.

Is differential remote sensing mandatory for MPQ8633B-HGLE-P operation?

No. RGND can be shorted to AGND or PGND if remote sensing is unused. However, doing so forfeits <±5mV load regulation; local sensing introduces up to ±25mV error at 20A due to PCB trace resistance, making differential sensing essential for precision core rails.

What is the maximum allowable voltage on the TRK/REF pin during normal operation?

The TRK/REF pin accepts 0.3V–1.4V for tracking or reference functions. Exceeding 1.4V risks damaging the internal amplifier; voltages below 0.3V disable tracking and may cause unstable soft-start. During startup, TRK/REF must exceed 600mV before VFB rises to ensure monotonic ramp.

Does MPQ8633B-HGLE-P support forced PWM mode at all load levels?

Yes. Configuring MODE pin with 30.1kΩ or 60.4kΩ to AGND forces FCCM regardless of load, eliminating PSM-related output voltage ripple modulation. This is required for noise-sensitive analog circuits but increases light-load quiescent current to ~850μA.

How is thermal shutdown recovery implemented in MPQ8633B-HGLE-P?

At TJ ≥160°C, the device shuts down and discharges TRK/REF capacitor. Recovery begins only after TJ drops to ≤130°C (30°C hysteresis), followed by automatic 1ms soft-start. No external reset is needed, but repeated cycling indicates insufficient PCB thermal design or excessive ambient temperature.