New Industry Products

TKD Unveils 12 New 5 to 25 Watt Board Mounted Class II Power Supplies

October 23, 2020 by Gary Elinoff

The KPSB6 and KPSB25 series of open frame, PCB mounted AC-to-DC power supplies operate over a wide temperature range

The new KPSB6 and KPSB25 series are both certified to the IEC 62368-1 standard for Audio/Video, Information and Communication Technology Equipment, and feature a Class II input requiring no earth ground. The units operate over an ambient temperature range of -40 to 80℃


Image courtesy of TDK
Image courtesy of TDK


All members of both series operate from input voltages of ranging from 90 to 264 VAC. The KPSP-6 series delivers 6 watts at 5, 9, 12, 15 or 24 volts and 5 watts at 3.3 volts. The KPSB-25 series supply 25 watts at 12, 15, 24, 36 or 48 volts and 20 watts at 5 volts.


Members of the PSB6 and KPSB25 series.
Members of the PSB6 and KPSB25 series. Modified diagram courtesy of TDK Data Sheet


For Both Series

Efficiency is as high as 87%. Line regulation is ±1%. The temperature coefficient is ±0.05.

The input to output isolation is 3,000 VAC and the touch current less than 250 µA.

The output voltages can’t be adjusted in either series, nor can the devices be operated in parallel. They can, however, operate in series, TDK recommends that users contact technical support for details.


Specifications specific to each Series


Offload Power Consumption

  • KPSB6:   less than 75mW 
  • KPSB25: less than 100mW


Output Accuracy at Full Load

  • KPSB6:   3.3V: ±6%, 5 to 9V: ±5%, 12 to 24V: ±3% 
  • KPSB25: 5V: ±2%%, 12 to 24V: ±1% 


Switching Frequency (typ)

  • KPSB6:  30 to 70 kHz
  • KPSB25: 65 kHz


Load Regulation (10 to 100% Load)

  • KPSB6:  5 to 9V: ±5%, 12 to 24V: ±3% 
  • KPSB25: 1%


Power Derating with Temperature

  • KPSB6:   As temperature rises from 60 to 80℃, power output for members of this series derate linearly from 100% down to 50%.
  • KPSB25:  As temperature rises from 50 to 70℃, for these units’ output derate linearly from 100% down to 50%.



These devices are suited to serve in the areas of:

  • Industrial control 
  • Factory automation
  • Building security
  • Instrumentation
  • Communications


Regulatory Compliance

As is the case for any device that plugs into the AV mains, the regulatory considerations are extensive and vary by jurisdiction. Some are listed below, with more complete listings available in the data sheet.

IEC/UL/CSA/EN 62368-1

They carry the CE mark for the Low Voltage, EMC and RoHS Directives.

IEC/EN 60335-1 (Household Appliances) 

IEC/EN 61558-1 (Transformer safety). 

EN 55024 and (Immunity)

Additionally, conducted and Radiated EMI radiation, concepts explained in our article “What Is the Difference between Conducted and Radiated EMI?", conform to EN55032-B standards. 


Physical Considerations

The devices are available in encapsulated or chassis mounted models with plug-in connectors as well as open frame board mounted configurations. The open frame members of the 6 watt KPSB-6 series and the 25 watt KPSB-25 series measure 39.5 x 19.4 x 18.3 and 50.8 x 27.94 x 24.9mm, respectively. 

The operating range for the KPSB6 is from -40 to +80°C, while the 25 watt devices operate over a span -30 to +70°C.