Technical Bulletin – February 2020

System Demystification III: Understanding Power Supply Operating Altitude Introduction From the capital of Tibet, to the once-bustling mining town of Leadville, Colorado, our planet’s mountainous terrain has not stopped mankind from settling down in some pretty altitudinous places. Residents of the world’s highest cities have acclimated to the decrease in pO2 , but design engineers […]

Technical Bulletin – December 2019

System Demystification II: Understanding Power Supply Inrush Current Introduction Knowledge of a power converter’s input current characteristics can prove useful for determining how many devices can be powered by a given electrical service/outlet without tripping breakers in the power system. Input current ratings given on switch-mode power supply (SMPS) nameplates are worst-case steady state figures […]

Technical Bulletin – November 2019

Power Supplies for Home Healthcare Applications: Implications of 60601-1-11 Introduction As our population grows and ages and the cost of in-hospital care continues to rise, modern technologies are developed to facilitate remote monitoring and remote care for today’s patients. Moving healthcare away from the hospital and into the home provides patients with both convenience and […]

Technical Bulletin – October 2019

Specification Demystification: Understanding Power Supply Hold-Up Time Introduction While many of the developed world’s power grids are robust and mature systems, they are not perfect. The mains voltage (available from the outlets in homes, offices, hospitals and other facilities), supplying power to the electrical devices we use every day, is vulnerable to a number of […]

Technical Bulletin – August 2019

Installation Considerations for Internal Power Supplies Introduction AC/DC power supplies can be classified into a broad array of genera depending on their physical construction and intended end use. These genera can be placed into one of two primary families, internal or external. Internal power supplies are those which, as the name suggests, will be installed […]

Technical Bulletin – July 2019

Burst-Mode Operation: A Double-Edged Sword Introduction In response to ever evolving power supply efficiency standards, power supply manufacturers are using burst-mode operation (amongst a sea of other energy saving strategies) to decrease the standby power consumption of external power adaptors. Efficient conversion techniques do not come without some cost. Burstmode operation can have adverse, and […]

Technical Bulletin – April 2019

Thermal Considerations for the Application of Power Converters Introduction One of the first questions one should ask themselves when selecting an appropriate AC/DC power supply for a given application is what sort of environment that device will be expected to operate in. A power supply that is intended to spend its operational life on the […]

Technical Bulletin – March 2019

The AC in Your DC: An Overview of Ripple & Noise Introduction The output of an AC/DC power converter is not necessarily a pure direct current waveform. In fact the DC output is actually a superimposition of some desired constant voltage and two AC artifacts known as ripple and noise. The relative magnitude of these […]

Technical Bulletin – February 2019

Loading Constraints: Understanding Maximum Capacitance Introduction The average PCB is home to an assortment of passive circuit elements, often including a broad array of capacitors of different types, ratings, and values. A capacitors sole function from a fundamental physical perspective is to store electric potential energy within an electric field between its electrodes. Circuit designers […]

Technical Bulletin – January 2019

The Case of the Missing Energy An Overview of AC/DC Conversion Losses Introduction What constitutes an ideal system? This is vague question that is sure to yield a multitude of different responses depending on who you ask. If you ask a power electronics engineer, they will probably tell you that an ideal system is one […]