Monolithic Power Systems Inc. EV2318-J-00A

Overview

EV2318-J-00A from Monolithic Power Systems is an evaluation board for the MP2318GJ synchronous step-down converter, configured to deliver 3.3V/2A output from 4.5–24V input, operating at fixed 2MHz switching frequency with internal 90mΩ/40mΩ MOSFETs and AAM-programmable power-save mode. It supports notebook I/O power, digital set-top boxes, and flat-panel display supplies.

For engineers reviewing the EV2318-J-00A datasheet, EV2318-J-00A pinout, EV2318-J-00A application, or EV2318-J-00A equivalent, this board enables rapid validation of MP2318GJ's transient response, efficiency across 5–24V input, thermal shutdown behavior, and enable/AAM control interface under real load conditions.

Technical Context

The EV2318-J-00A implements the MP2318GJ IC in a fully assembled TSOT23-8 layout with optimized 1μH power inductor (Wurth 744777001), 22μF input/output ceramic capacitors, and precision feedback resistors (R1/R2) setting VOUT = 3.3V. The board integrates AAM resistor (40.2kΩ) for PWM-only operation at VIN ≥12V and 100kΩ pull-up on EN for default-enable startup.

Test results confirm stable 3.3V regulation at 2A with ≤20mVpp output ripple (AC-coupled), <5% line/load regulation deviation, and thermal shutdown activation above 150°C junction temperature-verified using VIN = 19V, TA = 25°C boundary conditions per Rev.1.0 test report.

Key Specifications

Availability

EV2318-J-00A is available at Aetrix Electronics and suitable for notebook system power validation, digital TV auxiliary rail testing, and flat-panel monitor DC-DC design verification requiring stable component supply and documented reference performance.

Supply support for EV2318-J-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 power ICs, with over two decades of leadership in DC-DC conversion and motor driver solutions.

The MP2318 product line targets space-constrained, high-efficiency point-of-load applications in consumer electronics, delivering integrated 2A buck regulation in TSOT23-8 with minimal external components.

FAQ

What input voltage range is supported on the EV2318-J-00A board?

The board supports 4.5V to 24V DC input, as confirmed by test data across 5V, 12V, 19V, and 24V operating points in the Rev.1.0 report. Input capacitance uses dual 22μF X5R/X7R ceramics (C1/C2) rated for 25V/10V respectively, ensuring stability under worst-case surge and dropout conditions.

How is output voltage set, and can it be adjusted?

VOUT is fixed at 3.3V by the R1 (20kΩ) and R2 (6.34kΩ) resistor divider on the FB pin, per the MP2318GJ's 0.8V reference. Adjustment is possible by replacing R2: for example, 10kΩ yields ~4.0V. The board includes no solder jumpers or DIP switches-changes require discrete resistor replacement.

Does the board implement power-save mode, and how is it controlled?

No-R3 (40.2kΩ) ties the AAM pin to GND through a defined resistor, forcing continuous PWM operation per MP2318GJ datasheet behavior. To enable automatic power-save mode, R3 must be removed and AAM left floating or pulled up via higher resistance (e.g., 80.6kΩ for 5V input).

What is the purpose of the NS-marked resistor (R5) on the schematic?

R5 is marked "NS" (Not Stuffed) in the BOM and omitted from assembly. It provides optional placement for an external current-sense resistor to monitor inductor current, but the standard configuration relies on internal current-mode control without external sensing.

Can the EV2318-J-00A drive a 2A load continuously at 24V input?

Yes-test waveforms show stable 3.3V/2A output with ≤20mVpp ripple and no thermal shutdown under 24V input, 2A load, and 25°C ambient. Efficiency remains >85% per published curves, though board-level thermal margin requires adequate airflow or heatsinking for extended 24V/2A operation.

Is the EN pin active-high, and what logic levels are required?

Yes-EN is active-high with 1.6V minimum turn-on threshold and 0.9V maximum turn-off threshold, verified in startup/shutdown waveforms. It accepts standard 3.3V CMOS or open-drain 5V logic; no level-shifting circuitry is needed for direct microcontroller GPIO interfacing.