The patent mentions high frequency welding and furnaces, among other uses. 1926 On 23 June, British inventor Philip Ray Coursey applies for a patent in his country and United States, for his "Electrical Condenser". Variations of this ignition system were used in all non-diesel internal combustion engines until the 1960s when it began to be replaced first by solid-state electronically switched versions, then capacitive discharge ignition systems. The Kettering ignition system is a mechanically switched version of a fly back boost converter the transformer is the ignition coil. Kettering and his company Dayton Engineering Laboratories Company (Delco) goes into production for Cadillac. 1910 An inductive discharge ignition system invented by Charles F. History 1836 Induction coils use switches to generate high voltages. They are, however, more complicated switching currents can cause electrical noise problems if not carefully suppressed, and simple designs may have a poor power factor. Switching regulators are used as replacements for linear regulators when higher efficiency, smaller size or lighter weight is required. Despite the reduced transformer size, the power supply topology and the requirement for electromagnetic interference (EMI) suppression in commercial designs result in a usually much greater component count and corresponding circuit complexity. This is because it operates at a high switching frequency which ranges from several hundred kHz to several MHz in contrast to the 50 or 60 Hz mains frequency. Switched-mode power supplies can also be substantially smaller and lighter than a linear supply because the transformer can be much smaller. The switched-mode power supply's higher electrical efficiency is an important advantage. In contrast, a linear power supply regulates the output voltage by continually dissipating power in the pass transistor. Voltage regulation is achieved by varying the ratio of on-to-off time (also known as duty cycles). A hypothetical ideal switched-mode power supply dissipates no power.
Unlike a linear power supply, the pass transistor of a switching-mode supply continually switches between low- dissipation, full-on and full-off states, and spends very little time in the high dissipation transitions, which minimizes wasted energy.
Like other power supplies, an SMPS transfers power from a DC or AC source (often mains power, see AC adapter) to DC loads, such as a personal computer, while converting voltage and current characteristics. An adjustable switched-mode power supply for laboratory useĪ switched-mode power supply ( switching-mode power supply, switch-mode power supply, switched power supply, SMPS, or switcher) is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently. The coil and large rectangular yellow capacitor below the bridge rectifier form an EMI filter and are not part of the main circuit board. In close proximity, filter coils for the other secondaries Power supply with switching regulator Interior view of an ATX SMPS:īetween B and C: heat sink for switching active components of primary voltage īetween C and D: heat sink for switching active components of at least five secondary voltages, per the ATX specification ĭ: output filter coil for the secondary with the largest power rating.