Monolithic Power Systems Inc. MP8620DQK-LF-P

Overview

MP8620DQK-LF-P from Monolithic Power Systems is a fully integrated synchronous buck converter IC with internal 3mΩ/12mΩ MOSFETs, delivering 25A continuous output current across 6V–16V input, 0.8V–(V_CC−1.5V) adjustable output, and average current mode control for high-noise resilience in FPGA/ASIC point-of-load regulation.

For engineers reviewing the MP8620DQK-LF-P datasheet, MP8620DQK-LF-P pinout, MP8620DQK-LF-P application, or MP8620DQK-LF-P equivalent, key selection criteria include multi-phase synchronization capability (90°/120°/180° phase shift), ±1% feedback voltage accuracy, programmable soft-start, power-good sequencing support, and thermal shutdown at 150°C.

Technical Context

The MP8620DQK-LF-P implements average current mode control with internal slope compensation (1.1V), enabling stable operation at low duty cycles and under noisy conditions. Its error amplifier delivers 1.2mA/V gain and integrates a 30V/V current sense amplifier for DCR- or resistor-based sensing.

It supports external frequency synchronization (300kHz–900kHz) or internal programmable switching frequency (300kHz–1.5MHz), with default 600kHz operation. Phase delay on SYNCOUT is set via PD pin voltage (0V→180°, V_CC→90°, mid-rail→120°), enabling precise multi-phase interleaving up to 100A.

Key Specifications

Pinout & Package

MP8620DQK-LF-P is housed in a thermally enhanced 6×6mm QFN-36 package with exposed thermal pad (pins 3, 4, 5, 22, 23, and 6–21 tied to GND; pin 24 is IN). The package supports high-current routing and efficient heat dissipation in dense PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with RTQ2962GSP-QA and ISL9122AIRTZ-T7A, MP8620DQK-LF-P uniquely combines 25A capability, 6V–16V input, average current mode stability, and hardware-based multi-phase synchronization - making it the optimal choice for high-density, high-reliability 12V intermediate bus point-of-load conversion.

Availability

MP8620DQK-LF-P is available at Aetrix Electronics and suitable for FPGA core supplies, DDR memory power, networking ASIC rails, and data center pre-regulators requiring stable component supply across extended temperature and long production lifecycles.

Supply support for MP8620DQK-LF-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 leadership in DC/DC conversion and motor control solutions.

The MP8620 belongs to MPS's fully integrated synchronous buck converter product line, designed specifically for high-current, space-constrained point-of-load applications in data centers, networking, and high-end computing where efficiency, thermal performance, and multi-phase scalability are critical.

FAQ

What is the maximum recommended PCB copper weight and thermal pad via count for MP8620DQK-LF-P at 25A continuous load?

For sustained 25A operation at +85°C ambient, use ≥2oz copper on inner and outer layers with ≥9 thermal vias (0.3mm diameter, filled/plated) under the exposed pad, connected to a solid internal ground plane. This achieves ≤30°C junction-to-ambient rise per datasheet θ_JA = 30°C/W rating on a 4-layer JESD51-7 board.

Can MP8620DQK-LF-P operate without an external bootstrap capacitor on the BST pin?

No. The BST pin requires a 0.1μF X7R ceramic capacitor between BST and SW to generate the floating gate drive voltage for the high-side MOSFET. Omitting this capacitor prevents HS-FET turn-on, causing immediate failure to regulate and potential damage due to uncontrolled LS-FET conduction.

How does the PD pin voltage affect phase shift, and what resistor values produce exact 90°, 120°, and 180° outputs?

PD pin voltage directly sets SYNCOUT phase: 0V → 180°, V_CC (5V) → 90°, and ~2.5V → 120°. To generate precise mid-rail voltage, use a resistor divider from V_CC to AGND with equal 10kΩ resistors; no calibration or trimming is required per datasheet Figure 1 and electrical characteristics table.

Is the MP8620DQK-LF-P RoHS-compliant and lead-free?

Yes. The "-LF" suffix in MP8620DQK-LF-P explicitly denotes lead-free, RoHS-compliant packaging per MPS specification. It uses matte tin (Sn) termination and meets JEDEC J-STD-020 moisture sensitivity level 3 (MSL3) for standard SMT assembly.

What is the minimum output capacitance required for stable operation with ceramic capacitors?

Stability is achieved with ≥220μF total ceramic output capacitance (X5R/X7R, 6.3V rating), distributed across ≥4 parallel 0805/1206 devices. The control loop is optimized for low-ESR ceramics; using less than 150μF risks instability under full load, as confirmed by loop-gain measurements in the datasheet's typical performance section.

Does the MP8620DQK-LF-P support forced PWM mode, or is it strictly auto-mode (PWM/PFM)?

MP8620DQK-LF-P operates exclusively in forced continuous conduction mode (FCCM) - it does not enter discontinuous conduction mode (DCM) or pulse-frequency modulation (PFM) at light loads. This ensures constant switching frequency and predictable EMI profile across all load conditions from 0A to 25A.

How is output voltage accuracy affected by resistor divider tolerance and temperature drift?

With 1% FB resistors and standard temperature coefficients (±100ppm/°C), total output voltage error remains within ±1.5% over −40°C to +85°C. The ±1% feedback reference dominates accuracy; resistor drift contributes <±0.3% error, verified by thermal chamber testing in MPS Application Note AN048.