Monolithic Power Systems Inc. EVKT-8865

Overview

EVKT-8865 from Monolithic Power Systems is a complete evaluation kit for the MP8865GQ synchronous step-down converter, enabling rapid characterization of its I²C-programmable voltage regulation, frequency control, slew rate adjustment, and PFM/forced PWM mode selection under 4.5V–21V input and up to 6A output load conditions.

For engineers reviewing the EVKT-8865 datasheet, EVKT-8865 pinout, EVKT-8865 application, or EVKT-8865 equivalent, this kit provides full hardware-software integration with the MPS I²C GUI, USB-to-I²C interface (EVKT-USBI2C-02), and pre-layout MP8865GQ evaluation board (EV8865-Q-00A) for real-time register-level configuration and performance validation.

Technical Context

The EVKT-8865 integrates two physical modules: the EV8865-Q-00A evaluation board hosting the MP8865GQ IC in a 3x3 mm QFN-16 package, and the EVKT-USBI2C-02 USB-to-I²C bridge supporting PMBus-compatible communication at standard-mode (100 kHz) and fast-mode (400 kHz) speeds.

Hardware setup requires connection of SCL, SDA, and GND between the EVB and interface; software operation depends on Windows XP+ with .NET Framework 4.0 and the MPS I²C GUI, which reads/writes registers including VSEL, EN, OC/OT status flags, and switching frequency configuration bits.

Key Specifications

Availability

EVKT-8865 is available at Aetrix Electronics and suitable for power supply design validation, DC-DC converter qualification, and embedded system power architecture prototyping requiring stable component supply and repeatable lab evaluation capability.

Supply support for EVKT-8865 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 core expertise in DC-DC converters, LED drivers, and motor drivers for industrial, computing, and automotive applications.

The EVKT-8865 belongs to MPS's digital power evaluation platform family, designed specifically to accelerate adoption of I²C/PMBus-configurable buck converters like the MP8865GQ in space-constrained, high-efficiency power designs.

FAQ

Does the EVKT-8865 retain I²C register settings after power cycle?

No. All I²C-modified register values-including output voltage, switching frequency, and operation mode-are volatile and reset to factory defaults upon power-down. This behavior is inherent to the MP8865GQ's architecture and confirmed in Section 3.3 and warning notes of the User Guide Rev 1.1.

What is the required USB interface driver for EVKT-USBI2C-02?

The EVKT-USBI2C-02 requires the Silicon Labs USBXpress driver (v4.0.7.0 or later), installed via USBXpressInstaller_x86.exe or USBXpressInstaller_x64.exe. Driver version must match the OS bitness and appear as "USBXpress" under USB controllers in Device Manager.

Can the EVKT-8865 evaluate MP8865 variants other than MP8865GQ?

No. The EV8865-Q-00A board is specifically laid out for the MP8865GQ in QFN-16 (3×3 mm) package with defined pin mapping and compensation network. It does not support MP8865 variants with different packages, pinouts, or internal register maps.

Is external load required during evaluation?

Yes. A resistive or electronic load must be connected between VOUT and GND to validate regulation, transient response, and thermal performance. No-load operation is permitted only for basic communication and register-read verification per Section 3.2.

What happens if input voltage drops below 4.5V during operation?

The MP8865GQ activates its under-voltage lockout (UVLO) circuit: operation halts when AVIN falls below the UVLO falling threshold (~4.1V), and resumes only after AVIN exceeds the rising threshold (~4.5V), initiating a full power-on sequence with soft-start.

Where can the MPS I²C GUI software be downloaded?

The official MPS I²C GUI is available exclusively at https://www.monolithicpower.com/en/i2c-tool.html. The download link is located in the upper-right corner of the page; no registration or login is required for access.