More and more “catalog” or pre-manufactured power supplies are available from overseas with prices that seem too good to be true. Many bear all the right safety and EMC approval markings, yet upon investigation prove to be lacking.

We can get right to the heart of matter through careful inspection, testing and analysis and provide a detailed report. Aluminum capacitors overstressed by temperature and ripple current, magnetic cores overstressed by temperature and magnetic flux, overheated Schottky diodes leaking current in reverse – we can tell you where the weak points are that could reduce lifetime, fail a safety test or cause too much EMI – with or without a circuit schematic.


One important step is to open the case carefully, not only to avoid damaging the circuits inside, but also to maintain the enclosure for temperature testing.


The first tests performed are for steady state operation, power efficiency, CV/CC response then output short circuit and open circuit response. On the right a test jig for careful measurement of steady state output voltage ripple uses the original cable in order to include the effects of added resistance and inductance in the ΔVo tests.


Often the most important tests of all are for temperature. Here thermocouples are attached to all of the important powertrain components using special, thermally conductive glue.


For temperature testing a small hole is added and the thermocouples led out so that the case can be closed as much as possible. The goal is to test under the same airflow (or lack of airflow) conditions that the circuit sees in actual operation.