Monolithic Power Systems Inc. EV020A-5-S-00A

Overview

EV020A-5-S-00A from Monolithic Power Systems is an evaluation board demonstrating the MP020A-5 primary-side regulated flyback controller for universal-input (85–265VAC, 50/60Hz) 5W cell phone chargers. It delivers tightly regulated 5V/1A output without optocoupler or secondary feedback, integrates a 700V MOSFET, and achieves >70% full-load efficiency while meeting EN55022 conducted EMI and IEC61000-4-5 surge immunity.

For engineers reviewing the EV020A-5-S-00A datasheet, EV020A-5-S-00A pinout, EV020A-5-S-00A application, or EV020A-5-S-00A equivalent, this board enables rapid validation of primary-side control architecture, CC/CV regulation accuracy, low-noise transformer design, and multi-protection behavior-including OVP, OCP, OTP, and VCC UVLO-in compact AC/DC adapter designs.

Technical Context

The EV020A-5-S-00A implements a single-stage flyback topology with primary-side sensing via auxiliary winding voltage sampling (R5/R6 divider), eliminating secondary-side feedback components. Its MP020A-5GS IC uses variable off-time, peak-current control and a 550µA high-voltage startup current source to enable direct AC line connection.

EMI performance is enhanced by natural spectrum shaping, a π-filter input stage (C1/L1/C2), Y-capacitor (CY1) for common-mode suppression, and snubber network (R2/R3/D1/C3). Protection functions include cycle-by-cycle current limiting, open-circuit and short-circuit detection, and thermal shutdown triggered by internal die temperature monitoring.

Key Specifications

Availability

EV020A-5-S-00A is available at Aetrix Electronics and suitable for cell phone charger development, handheld electronics adapter qualification, and auxiliary power supply prototyping requiring stable component supply and reference-grade validation data.

Supply support for EV020A-5-S-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 expertise in DC/DC conversion, LED drivers, motor drivers, and AC/DC controllers.

The EV020A-5-S-00A belongs to MPS's primary-side regulation evaluation platform family, designed to accelerate adoption of optocoupler-free, low-BOM-cost flyback solutions for consumer charging and auxiliary power applications.

FAQ

What is the purpose of the EV020A-5-S-00A evaluation board?

This board demonstrates the MP020A-5GS primary-side regulator IC in a complete, tested 5W flyback charger design. It validates key features including optocoupler-free CC/CV regulation, <30mW no-load consumption, EN55022-compliant EMI performance, and robust protection schemes under universal AC input conditions.

Does the board include safety agency certification?

No. The EV020A-5-S-00A is an engineering prototype not certified to UL, CE, or other safety standards. Per MPS documentation, all testing must use an isolation transformer on the AC input, and the board is intended solely for lab evaluation-not end-product integration without additional safety qualification.

How is output voltage regulated without secondary feedback?

Voltage regulation is achieved by sampling the reflected auxiliary winding voltage during the flyback demagnetization period. The MP020A-5GS uses this sampled signal-scaled by R5/R6-to maintain precise 5V output via variable off-time control, eliminating the need for optocouplers or TL431-based feedback networks.

What transformer is used, and why is its construction critical?

The board uses Wurth EE16 transformer 7508110157 with triple-insulated secondary windings (NSEC1/NSEC2), 1.6mH ±10% primary inductance, and 3000VAC isolation between primary and secondary. This construction ensures safety compliance, minimizes leakage inductance (<50µH), and enables clean EMI performance essential for Class B conformance.

Can the board be modified for different output voltages?

Yes-output voltage is set by the R5/R6 resistor divider ratio on the auxiliary winding. Adjusting these values recalibrates the sensed voltage threshold, enabling reconfiguration for other constant-voltage outputs (e.g., 9V or 12V), provided transformer turns ratio and output rectification are adapted accordingly.

What protections are implemented, and how are they triggered?

Protections include overvoltage (OVP) via auxiliary winding over-sampling, overcurrent (OCP) via primary peak current limit, open-circuit (OCkP) detection during prolonged demagnetization, overtemperature (OTP) via internal thermal sensor, and VCC undervoltage lockout (UVLO). All are hardware-based and respond within one switching cycle.