New Industry Products

RECOM Debuts Three 5-Watt Single Output AC/DC Converters

August 11, 2021 by Gary Elinoff

The new units operate from 100 to 270VAC inputs and provide either 5V, 12V, or 15V outputs.

RECOM’s RAC05-K/PD3/H series are single output, board-mounted converters that are IEC61010 safety rated to PD3 and OVCIII by UL.

Image courtesy of RECOM

While nominal input ratings are from 100VAC to 277VAC, the converters will nonetheless withstand a continuous 480 VAC input without damage. No-load power consumption is less than 0.5 watts, and critically, they meet EN 55032 Class B EMI emissions level (floating output), with no extra external components.


The Converter Series is Aimed at Tough Operating Environments

The board-mounted devices are intended for ‘fixed installations’ where higher levels of voltage transients, according to over-voltage category III (OCVIII), are experienced. Accordingly, the units meet OVCIII up to 5000m altitude. They are also specced to operate in tough “Pollution Degree 3” (PD3) environments, where the pollution if condensation occurs, can become destructively conductive.

Michael Schrutka, RECOM AC/DC product manager comments “Our new 5W AC/DC converters provide real value when compliance with over-voltage category III is required especially along with higher levels of protection against ambient air pollution in harsh environments. By eliminated or at least significantly reduced the need for external suppression components.


The Three Series Members

  • RAC05-05SK/PD3/H supplies 5 volts at 1 amp. Maximum efficiency is 73% and the maximum capacitive load is 10,000µF
  • RAC05-12SK/PD3/H is a 12-volt device that supplies 420mA with 74% maximum efficiency. The maximum capacitive load is 1,200 
  • RAC05-15SK/PD3/H supplies 15 volts at 330mA to a maximum capacitive load of 1,000µF. Maximum efficiency here too is 74%


Basic Specifications

The converters operate at 47 to 63Hz. Input current at 100VAC and 277VAC are 110mA and 60mA, respectively. Inrush current, at 25℃, is 20 amps. These units need no minimum load to operate properly.

With inputs ranging from 230VAC to 277VAC, the minimum power factor is 0.50. The typical start-up time is 25ms, and the maximum rise time is 20ms.

Holdup times (typical) at different voltage inputs are:

  • 110VAC is 14ms
  • 230VAC is 50ms
  • 277VAC is 60ms

The switching frequency is 130kHz.

Output ripple and noise, over a 20MHz bandwidth with an input voltage of 277VAC, is 50mVp-p.


Voltage Regulation

Typical responses are:

  • Output Accuracy is ±1.0% 
  • Line Regulation is ±0.5% 
  • Load Regulation, for a load shift from 10% to 100%, is 1.0%

Transient Response

  • For a 25% step change, transient response is a maximum of 4%, with a typical recovery time of 500µs



  • Isolation Voltage from input to output for 1 minute is 5.4kVAC
  • Isolation Resistance is a minimum of 1GΩ
  • Isolation Capacitance is a maximum of 100pF
  • Leakage Current is a maximum of 25µA max



  • There is a slow burn, 2 amp, 350VAC external fuse
  • Short circuit protection (SCP) is of hiccup mode type with automatic restart and kicks in at 100mΩ
  • Over voltage and over current protection are both also hiccup mode and both activate at from 150% to 195%



  • Renewable energy
  • Smart grid
  • IoT systems
  • Smart metering
  • Monitoring food and beverage processing appliances


Physical Considerations

  • The new units operate over a temperature range of -40°C to +85°C 
  • The converters are available in 2” x 1” x 1” packages


Regulatory and Safety

A complete listing of regulatory safety certifications can be found on the datasheet. Highlights include:

  • IEC/EN 62368-1
  • UL 61010-1