MEAN WELL IRM-03-9S 3W 9V DC PCB Mount Encapsulated AC-DC Power Supply Module

Embedded systems engineers integrating a compact power stage into IoT sensors, smart home controllers, or industrial monitoring nodes will appreciate the IRM-03-9S as a board-level AC-DC converter that delivers a stable 9 V DC rail from universal mains input. Its fully encapsulated plastic case and PCB-mount footprint simplify assembly in space-constrained designs.

Key specifications

• Output: 9 V DC, 0.33 A, 3 W maximum power
• Input: 85–305 VAC (120–430 VDC), suitable for worldwide use
• Efficiency: 78% typical; no-load consumption below 0.075 W
• Isolation: 3000 VAC between input and output
• Protection: short circuit, overload, over voltage
• Ripple & noise: 80 mVp-p; line regulation ±0.5%; load regulation ±1.0%
• Operating temperature: -30 °C to +70 °C, free air convection cooling
• Certifications: UL62368-1, TUV EN62368-1, EAC, CE; MTBF > 480,000 hours

Why choose it

The IRM-03-9S eliminates the need for a separate external power brick, reducing bill of materials and assembly time. Its encapsulated design protects against dust, moisture, and mechanical stress, while the wide input range ensures consistent operation even in areas with unstable mains voltage. The low no-load power draw helps meet energy-efficiency regulations.

Ideal use cases

• Powering sensors, microcontrollers, and low-power wireless modules in smart building systems
• Industrial control boards, timers, and small automation devices
• Home appliances and consumer electronics requiring an integrated power supply
• Replacement or upgrade for linear transformer-based supplies in legacy equipment

Good to know

The module is designed for PCB mounting and requires adequate clearance for heat dissipation. It is not intended for outdoor use without additional enclosure. Always follow local electrical safety regulations during installation.