Monolithic Power Systems Inc. MP8720GQ-P

Overview

MP8720GQ-P from Monolithic Power Systems is a synchronous buck converter IC delivering up to 10A continuous output current with adjustable valley current limit (8.5A–16.5A), fixed 700kHz switching frequency, and adaptive constant-on-time (COT) control for fast transient response in DDR memory and USB Type-C power rails. It integrates high- and low-side MOSFETs (R_DS(ON) = 19mΩ/7mΩ), DC auto-tune loop, and full protection suite including OCL, OVP, UVP, and thermal shutdown.

For engineers reviewing the MP8720GQ-P datasheet, MP8720GQ-P pinout, MP8720GQ-P application, or MP8720GQ-P equivalent, key selection considerations include its QFN-16 (3mm×3mm) package, CLM-adjustable current limit, dual-mode (CCM/DCM) operation via MODE pin, stable ceramic capacitor compatibility, and pre-bias start-up capability in embedded power systems.

Technical Context

The MP8720GQ-P implements adaptive COT control with internal ramp compensation, enabling stable regulation without external ESR-dependent output capacitors-supporting pure ceramic solutions. Its valley-current sensing OCL uses the integrated low-side MOSFET's R_DS(ON) as the current-sense element, eliminating external sense resistors.

DC auto-tune loop dynamically adjusts control parameters to maintain tight line and load regulation across input (4.5V–26V) and output (0.8V–5.5V) ranges. The CLM pin sets four discrete current-limit thresholds (8.5A/10A/13A/16.5A) via resistor-to-GND, while MODE pin selects CCM/DCM and output voltage range (≤3V or ≥3V) simultaneously.

Key Specifications

Pinout & Package

MP8720GQ-P is housed in a thermally enhanced QFN-16 (3mm × 3mm) package with an exposed thermal pad (EP) on the bottom for PCB-level heat sinking. Pin 1 is marked by a dot or beveled corner; pins are numbered counter-clockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2315GJ-Z, MP8720GQ-P delivers 67% higher current capacity and field-programmable OCL-critical for USB-C multi-port scaling. Versus RT7297BZSP, it eliminates the external sense resistor and BST cap, reducing layout complexity and improving reliability in high-volume production.

Availability

MP8720GQ-P is available at Aetrix Electronics and suitable for DDR memory power supplies, USB Type-C sink implementations, and distributed power systems requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP8720GQ-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 over two decades of innovation in DC-DC conversion and motor control.

The MP8720 belongs to MPS's high-current synchronous buck converter product line, engineered specifically for high-density, fast-transient power delivery in memory interfaces and USB-C infrastructure-emphasizing integration, thermal robustness, and ease of system validation.

FAQ

What is the minimum recommended output capacitance for stable operation?

The MP8720GQ-P is stable with ≥22µF total ceramic output capacitance (e.g., three 22µF X5R 0805 caps). Internal ramp compensation eliminates ESR dependency, so POSCAP or polymer capacitors are optional. Layout best practices require placing capacitors within 3mm of the FB and PGND pins to minimize loop inductance and avoid instability.

Can MP8720GQ-P operate with a pre-biased output?

Yes-MP8720GQ-P supports pre-bias start-up. When EN is asserted while VOUT is already charged, the IC disables both high- and low-side switches until the internal reference voltage exceeds the sensed FB voltage. This prevents reverse current flow and ensures monotonic output ramp-up without overshoot or oscillation.

How does the CLM pin affect over-current protection behavior?

The CLM pin sets the valley current limit threshold used in cycle-by-cycle OCL detection. With CLM grounded (8.5A), the LS-FET's R_DS(ON) is monitored during its on-time; if sensed current exceeds the threshold, the next HS-FET turn-on is blocked. This is non-latching-protection resets each cycle unless UVP triggers due to sustained overload-induced voltage collapse.

Is an external bootstrap capacitor required, and what value is recommended?

Yes-an external 0.1µF X7R ceramic capacitor is mandatory between BST and SW pins. It must be placed within 2mm of the IC with short, direct traces to sustain gate drive voltage for the high-side MOSFET. Larger values (>0.22µF) do not improve performance and may slow bootstrap recharge, risking shoot-through under heavy load.

What thermal derating applies above 85°C ambient temperature?

With standard 4-layer JEDEC PCB (2oz copper, 1in² thermal pad), MP8720GQ-P delivers full 10A up to +85°C ambient. Above that, current must be linearly derated using θ_JA = 55°C/W: maximum allowable power dissipation drops by ~18mA/°C. At +105°C ambient, max continuous output current is ~7.3A to maintain T_J ≤ 125°C.

Does MP8720GQ-P support forced PWM (FPWM) mode?

No-MP8720GQ-P offers selectable pulse-skipping (DCM) or forced CCM only via the MODE pin; it does not implement true FPWM (constant-frequency, variable-duty-cycle) across all loads. In CCM mode, switching frequency remains ~700kHz regardless of load, but light-load efficiency is lower than DCM due to fixed switching losses.

How is power-good (PG) timing affected by soft-start duration?

PG asserts high 1.8–2.6ms after EN rises-matching the soft-start ramp time. The PG signal remains low until VFB reaches 95% of VREF, then transitions high within 3µs. During shutdown, PG pulls low within 1µs of EN deassertion, providing precise sequencing for downstream logic and LDOs.