Monolithic Power Systems Inc. EV161-S-00A

Overview

EV161-S-00A from Monolithic Power Systems is an evaluation board designed to demonstrate the MP161AGS-5 primary-side constant voltage regulator IC, which integrates a 700V switching regulator, low-dropout linear regulator (5V output), and dual-channel relay drivers in SOIC-16. It delivers 12V/70mA and 5V/50mA outputs from 85–265VAC input, supports buck topology, achieves ≤16mW no-load consumption, and meets IEC61000-4-5 (2kV) surge and EN55022 conducted EMI standards for home/industrial automation power supplies.

For engineers reviewing the EV161-S-00A datasheet, EV161-S-00A pinout, EV161-S-00A application, or EV161-S-00A equivalent, this page provides verified board-level specifications, functional test results, thermal and EMI performance data, safety-critical operating constraints, and direct integration guidance for relay-driven MCU systems requiring ultra-low standby power and optocoupler-free CV regulation.

Technical Context

The EV161-S-00A implements a primary-side-controlled buck converter using the MP161AGS-5, eliminating optocouplers via internal loop compensation and peak-current modulation for audible-noise suppression. Its architecture enables accurate 12V CV regulation across universal AC input while maintaining cross-regulation between 12V and 5V outputs.

Board-level features include π-filter (C4/L1/C5) for EN55022 compliance, STTH1R06 freewheeling diode rated for 600V reverse voltage, self-locking push-button controls (SW1–SW3) for STBY/INA/INB logic, and discrete 100μF/25V + 1μF ceramic output capacitance on the 12V rail to suppress low- and high-frequency ripple respectively.

Key Specifications

Availability

EV161-S-00A is available at Aetrix Electronics and suitable for home automation gateways, industrial PLC I/O modules, and smart appliance control boards requiring stable component supply, rapid power architecture validation, and regulatory-compliant AC/DC reference designs.

Supply support for EV161-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 core expertise in DC/DC conversion, LED drivers, and motor control solutions.

The MP161 product line targets cost-sensitive, space-constrained AC/DC applications needing optocoupler-free constant voltage regulation-specifically for relay-based control systems in home and industrial automation where standby power and EMI are critical.

FAQ

Is EV161-S-00A isolated or non-isolated?

EV161-S-00A is a non-isolated evaluation board. All high-voltage nodes-including L, N, VOUT1, and relay coil terminals-are referenced to the same ground plane. Users must employ an isolation transformer during testing and avoid contact with any exposed conductors when powered.

What IC is mounted on EV161-S-00A, and what package does it use?

The board uses the MP161AGS-5 IC in SOIC-16 package. This device integrates a 700V switching regulator, 5V LDO, and two relay drivers with 2Ω on-resistance and integrated freewheeling diodes-enabling direct drive of 12VDC relays like the included 307HN-1AH-F-S.

How is standby mode activated and verified on this board?

Standby mode is engaged by pressing SW1, which pulls the STBY pin low; recovery occurs upon release. During standby, no-load consumption drops to ≤16mW, and VOUT1/VOUT2 remain regulated. Waveform validation (Fig. 8) confirms clean entry/recovery transitions with no output dropout or oscillation.

Can EV161-S-00A evaluate MP161 variants other than MP161AGS-5?

Yes-the board is compatible with MP161B and MP161C variants per documentation. Differences in fixed vs. adjustable output configuration or protection thresholds do not affect mechanical or functional compatibility, as all share identical SOIC-16 pinout and core architecture.

What safety precautions apply when operating EV161-S-00A?

Due to its non-isolated topology, the board must be powered via an isolation transformer. All measurements involving oscilloscope probes require differential or isolated inputs. The warning label on page 7 mandates strict adherence to creepage/clearance limits and prohibits user modification of safety-critical components (e.g., F1, C4, C5, D5).

Does EV161-S-00A support both relay channels simultaneously?

Yes-SW2 and SW3 independently control INA and INB pins, enabling concurrent activation of Relay1 and Relay2. Each driver supports 30V rail voltage and includes integrated freewheeling diodes; the board's schematic (Fig. 1) confirms separate OUTA/OUTB outputs routed to distinct relay coils.