TDK Unveils a series of 30 Watt Medical and Industrial DC-DC converters

December 13, 2020 by Gary Elinoff

The new series of board mounted devices feature 4:1 input ranges and 5K VAC reinforced isolation

Individual members of the PXD-M30 series can operate over input voltage ranges of either 9 to 36 VDC or 18 to 75 VDC. Dual and single output units supply 5, 12, 15, 24, ±5, ±12 and ±15 VDC. 


Image courtesy of TDK
Image courtesy of TDK


The PXD-M30 series includes 14 members, six with dual outputs and eight with single outputs.


Image courtesy of of PXD-M30 Data Sheet
Image courtesy of of PXD-M30 Data Sheet


4:1 Input Ranges

The “4:1” specification comes from the observation that 36 volts is 4x 9 volts, and 76 volts is 4x 18 volts. These wide input ranges, covering the popular 12, 24 and 48 VDC input voltage rails, means that OEMs will need to inventory fewer parts to cover a wider range of design mandates.


Reinforced Isolation

Isolation is meant to allow communication between two parts of a system, and to block the transfer of DC or unwanted AC noise. Modern electronic systems often feature multiple grounds and power supplies, and isolation can help to avoid the ground loops that can occur in the absence of proper isolation.


Basic Isolation is one level of protection 


 Single Isolation.
 Single Isolation. Image source TI Video


Double Isolation refers to two separate single isolators. 


Double Isolation.
Double Isolation. Image source TI Video 


Reinforced Isolation features a single isolation layer that is the equivalent to a double isolation system.


Reinforced Isolation.
Reinforced Isolation. Image source TI Video


Members of the PXD-M30 series offer reinforced isolation, and feature input to output isolation of 5,000 VAC.


Important Specifications

Output Voltage Adjustment

The single output devices are adjustable as follows:

  • 5 Volt: 4.5 -5.5 Volts
  • 12 Volt: 10.8 – 13.2 Volts
  • 15 Volt: 13.5 – 18 Volts
  • 24 Volt: 21.6 – 28.8 Volts 


The dual output units are not adjustable

Switching Frequency: 225 to 285 kHz

Output Voltage Tolerance: ±1%


  • Single output units feature ±0.2% line and load regulation
  • Dual output units feature: ±0.5% line regulation and ±1.0% load regulation


Transient Loading: There is a 250us recovery time for a 25% load change 


Overcurrent Protection: Hiccup mode at 150 to 185%

Overvoltage protection (typical): 

  • 5 Volt units: 6.2 Volts
  • 12 Volt units: 15 Volts
  • 15 Volt units: 20 Volts
  • 24 Volt units: 30 Volts 


Multiple units can be operated in series, but parallel operation is not possible 


Applications Include:

  • Medical devices
  • Home care
  • Laboratory equipment
  • Industrial applications
  • Test and Measurement
  • Communications
  • Broadcast


Regulatory and Safety Considerations

Members of the PCD-M30 series feature:

  • Input to output isolation of 5,000 VAC (2 x MOPPs)
  • Under 2.5μA touch current

Safety certifications adhered to include:

  • IEC/UL/CSA/EN62368-1

EMI standards met with no need for external components 

  • EN55032-A
  • EN55011-A

Additionally, the units feature CE marking for the Low Voltage and RoHS Directives


Physical Considerations

All members of the series:

  • Are available in an industry-standard 2 by 1 inch package
  • Typical weight is 32 grams
  • Operate over a -55 to +105℃ temperature range. Output voltage derate linearly 
    • From +40 to 105 ℃ with convection cooling
    • From +73 to 105 ℃ with forced air (200 LFM) cooling
  • Tolerable humidity is from 5 to 95%
  • Vibration and thermal shock as per MIL-STD-810F