Monolithic Power Systems Inc. EV9485-N-00A

Overview

EV9485-N-00A from Monolithic Power Systems is an evaluation board designed to demonstrate the MP9485 4.5V–100V input, 500mA synchronous step-down converter with hysteresis control, 5V fixed output, and SOIC8-EP package. It integrates a high-side 100V MOSFET with >0.75A current limit and achieves up to 92% efficiency at 36V_IN/5V_OUT/500mA. Used for rapid validation of wide-input industrial and automotive power supplies.

For engineers reviewing the EV9485-N-00A datasheet, EV9485-N-00A pinout, EV9485-N-00A application, or EV9485-N-00A equivalent, this board enables fast functional verification of MP9485's transient response, hiccup-mode short-circuit protection, thermal shutdown behavior, and 170μA quiescent current in real-world 8–95V input systems.

Technical Context

The EV9485-N-00A implements a fixed 5V output configuration using the MP9485 IC, which employs proprietary hysteresis voltage-mode control-eliminating external compensation components and enabling sub-1μs load transient response. Input range is validated from 8V to 95V DC, with startup requiring ≥8V to ensure sufficient bootstrap capacitor (BST) voltage.

Board-level design includes a 33μH shielded inductor (Wurth 7447714330), B1100 Schottky diode, 100μF tantalum output capacitor, and precision feedback resistors (R1=240kΩ, R2=10kΩ) setting V_FB=0.2V. EN pin supports logic-level on/off control with 1.7V turn-on threshold and <1V shutdown threshold.

Key Specifications

Availability

EV9485-N-00A is available at Aetrix Electronics and suitable for scooter control power supply design, solar energy system auxiliary rails, and automotive body electronics requiring stable component supply across extended input voltage ranges.

Supply support for EV9485-N-00A 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 mixed-signal ICs for power management, motion control, and interface applications.

The MP9485 product line targets high-voltage DC/DC conversion in harsh environments-designed specifically for industrial, automotive, and renewable energy systems needing robust 100V-rated buck regulation with minimal external components.

FAQ

What input voltage range is validated for reliable operation?

The EV9485-N-00A board is validated for continuous operation from 8V to 95V input. Below 8V, bootstrap capacitor charging becomes insufficient, causing startup failure or erratic switching. The underlying MP9485 IC supports 4.5V–100V, but board-level component ratings and layout constraints fix the practical lower limit at 8V.

How is output voltage adjusted, and what is the feedback reference voltage?

V_OUT is set by resistor divider R1 (240kΩ) and R2 (10kΩ) on the FB pin, yielding 5V with V_FB = 0.2V. To change output, use V_OUT = 0.2V × (1 + R1/R2); R1 remains fixed, so only R2 is modified. The board includes test points for direct FB node access and optional R2 replacement.

Does the board support enable/disable functionality, and what are the logic thresholds?

Yes-EN pin (Pin 6 of U1) provides active-high enable control. Applying >1.7V turns on the MP9485; <1V disables it. During disable, V_OUT discharges to 0V through the load. The board routes EN to a test point and includes a 0Ω jumper option for permanent enable if needed.

What protection mechanisms are implemented and how do they behave under fault?

The board demonstrates MP9485's hiccup-mode short-circuit protection: upon overcurrent, switching halts, then restarts after a cooldown interval. Thermal shutdown activates above 150°C junction temperature and releases automatically once cooled. Both protections are fully autonomous-no external circuitry required.

Can this board be used to evaluate efficiency across input voltages?

Yes-the provided efficiency vs. load curves cover VIN = 36V and 60V, and test data confirms >85% efficiency from 10mA to 500mA across 8–95V inputs. Board layout includes Kelvin-sense pads for accurate input/output power measurement, supporting precise efficiency characterization per JEDEC JESD51 standards.

Is the MP9485 IC on this board lead-free and RoHS-compliant?

Yes-MP9485 is lead-free, halogen-free, and fully compliant with EU RoHS Directive 2011/65/EU. All passive components on EV9485-N-00A-including muRata capacitors, Wurth inductors, and Diodes Inc. B1100-carry RoHS-compliant part numbers and are marked accordingly in the BOM.