Electronic design service, military power conversion.

Power For Military Applications.



Peritus Power has more than 12 years of experience in the field of power for military applications. The list below details some of the supplies that have been designed and reached production, many of which are currently still in production. The identity of the end user is classified for some products.


  • Full suite of 28V DC DC converters for FLIR (Forward Looking Infra Red), used on thermal imaging equipment for Air force, Navy and Army.

  • 28VDC to 100VAC converter for cooling engine electronics in the same FLIR.

  • Various multiple output very low profile DC DC converters for video recoding surveillance in unmanned drones.

  • Multiple output supplies for IFF, Identify Friend Or Foe.

  • Various supplies for Direct Infra Red Counter Measure electronics, (DIRCM), also named Nemesis.

  • High reliability intelligent battery charger for land based vehicles.

  • High voltage 3 phase 400Hz AC AC converter, used as line conditioner for cooling FLIR equipment.

  • High efficiency, very high reliability power supplies for location on the sea bed underneath oil rigs.

  • Other designs cannot be listed or mentioned due to the classified nature of those products.

Advice is available on the extreme temperature requirements for this industry, full operation down to -55C to 125 or 150C has been successfully achieved many times, as well as surviving violent vibration profiles, as seen in the proximity of aircraft cannon gun fire.

The services offered in the design , consultancy and RCA sections of this web site apply to this military section also. Familiar with all the reliability Mil217 type documents, and other military power requirements. Peritus Power also retains links with current military sub-contractors, enabling the support of an entire solution, electronic and mechanical. We also have the expertise in plastic industrial semiconductor packages.

In the mid 1990's we were responsible for the main work carried out by the MoD to study the feasibility of plastic packages, as a cost reduction to the more expensive hermetic parts. So successful was this task, designs that followed on used plastic packages as opposed to hermetic. Although this rule does not apply to every component, more than 90% of semiconductor components are now plastic packaged.

Input Power Supply For Military Applications.



Military power designs surround various inputs, 12V, 28V, -48V, 115V single phase or 3 phase, high voltage DC and the list goes on. Some designs target low voltage DC 15V to 32V, whilst others may be 208V to 600VAC 45Hz to 65Hz. These type of designs usually have an automatic phase lock and will report phase problems, such as phases down. Other designs target a 115V to 960V 3 phase 50Hz, 60Hz or 400Hz frequency. The input considerations and requirements are vast and as such each design is fairly unique compared to the commercial industry of 90VAC to 264VAC single phase and the 415V 3 phase designs.

These designs have to use commercially available parts, the high voltage designs present safety and EMI problems, especially around adequate EMI filtering whilst retaining safe leakage current levels. Creepage and clearance can be space consuming providing another technically challenging aspect of the design. Military electronics does impose the same reduction in space as commercial designs, but as the performance criteria is usually more demanding, this presents what can at times be huge challenges.
Power Factor Correction is an area that has to be carefully controlled. Aircraft electronics supply 115VAC 400Hz. The high line frequency can prove demanding, sources of current harmonic distortion results in system power related problems, particularly with the dynamic interactions between the AC source and the PFC converters. These undesirable effects can be reduced or eliminated with good PFC filters, sometimes at a cost in efficiency. The overall gain in system power quality out weighs the disadvantages in efficiency losses, as these losses should be small.

Output Characteristics.



Output power levels are diverse, from milliwatts to megawatts. Of more importance is output noise and ripple, sometimes referred to as PARD, Periodic And Random Deviation. PARD is usually defined within the bandwidth of 10Hz to 20Mhz, usually encompassing common mode and differential.

Modern designs of high frequency, and lower operating voltages generally in electronics contribute to PARD being even more important. Due to signal to noise ratios, especially within the I2C communication require PARD to be controlled and measured over much higher bandwidths. Specifications vary, but bandwidths up to 500Mhz are becoming more common. There does appear to be a direct link to high noise in the upper frequency ranges and I2C errors.
Measurement techniques are equally important, the measurement methodology has to be such that the results demonstrate the true noise being measured, and not include noise picked up through the test set up cables. Attention has to be paid to line attenuation or shielding, otherwise testing will produce widely inaccurate data, due principally to the common mode noise being directly coupled into the measurement cable, whilst the AC PARD is generally an AC differential signal.

Extended Environmental Operation.



Military electronics, particularly uninhabited environments, require full operation as low as -55C and as high as +150C. This criteria usually stipulates full operation to specification over these limits. With no fans allowed in much of the equipment, cooling is generally based on the "cold wall" technique. Attention to detail is paramount in thermal junction and case temperatures, all components within the supply must be available from the manufacturer at military temperature grades.

There are two main challenges to this, firstly components must be capable of the -55C to 150C requirement, but the internal ambient could be 15C higher.
Cold start up conditions can be problematic, with stability challenging, the parameters of each component will change radically over the temperature extreme.
Mechanical design is just as important With violent vibration profiles simulating rapid canon gun fire, designs have to capable of full operation without internal or external damage. Designs not meeting the grade will witness broken connectors, PCB's, broken component legs, ceramic capacitors, and broken magnetics. All this can lead to damaged and blown up systems.
Contact Peritus Power to discuss military power requirements, sub contractor availabilities and consulting services.