HP HP-Bench-Briefs-1978-11-04 free download

File name HP-Bench-Briefs-1978-11-04.pdf

6% Technical Training - page. 11 a SERVICE INFORMATION FROM HEWLETT-PACKARD NOVEMBER 1978-APRIL 1979 Switching Power Supplies Editor`s note: The material for this article This last category is by far the most Within each type of power supply, was edited from H P s DC Power Supply common of the four and is generally different forms of regulation are I ~ & o (AN ~o 9oB)j OrigkllY written the one referred to when speaking of used to maintain a constant output. by Richard Tomasetti of the Marketing a ttpower supply.^^ Switching is one of the forms used in Communications group at H P s power a constant voltage power supply. supply division in Rockaway, New r-----. YtVSVJf. Four basic outputs or modes of operation can be provided by dc out- Electronic power supplies are de- put power supplies: fined as units that convert power from an ac or dc source into ac or dc Constant Voltage: The output power at voltages suitable for sup- voltage is maintained constant in plying an electronic device. spite of changes in load, line, or temperature. Within this definition, electronic Constant Current: The output power supplies can be divided into current is maintained constant in four broad classifications: spite of changes in load, line, or (1) ac in, ac out - line regu- temperature. lators and frequency changers Voltuge Limit: Same as Constant (2) dc in, dc out - converters Yoltage except for less precise and dc regulators regulation characteristics. (3) dc in, ac out - inverters Current Limit: Similar to Con- (4) ac in, dc out - "common" stant Current except for less ipre- power supply cise regulation. * I .- SWITCHING POWER SUPPLIES operation at power line frequencies. Typically, a switching supply is less that substantially than one-third sim and weight of a 1 c o n b l output ripp ching Regulated