The SW series precision switching high voltage power supplies are highly efficient DC to DC converters designed for applications such as CRT displays which require a highly regulated source of high voltage. Since these models use state of the art switching circuitry, as opposed to older linear designs, the input current into the power supply is greatly reduced. This has a profound effect on the reliability of the unit, and since the power dissipation is low, operation at ambient temperatures to 85 deg C case is possible.
The input ports are transient protected by the use of suppressor diodes. An output arc to any input will not damage the supply. The output voltage is adjustable down to 10% via a 20 turn potentiometer located on the front of the power supply. In addition, the output may also be adjusted by an external control voltage to ground. Placing an input voltage up to +13 VDC on Pin 2 will lower the output. The connecting and control pins are all accessible via the front as well.
The SW Series high voltage power supplies are regulated by virtue of Pulse Width Modulation topology. The normal input voltage of 28 VDC is stepped up by resonant action to a high voltage output which is referenced to the input ground. The output voltage of the SW unit is NOT FLOATING. The output high voltage return and the input power return are internally connected together.
The output voltage may be controlled using a reference voltage. Here, a control voltage between 0 - 13 VDC will adjust the output between full and zero output.
The maximum output current ability is set for each unit at approximately 130% above the values dictated by the maximum power at full output. Drawing more than this amount will activate the “try again” current limit circuitry which protects the high voltage power supply. Here, during a short or overcurrent condition, the power supply shuts down for 2 seconds and then “retries”. If the short is still present, the power supply simply retries over and over again until the short is removed.
Negative output units are designated by an “N” after the number in the model name.
