SQ Series

Electrical Characteristics & Description
The SQ Series compact high voltage power supply is a low input current version of the SC series. The typical input current for an SQ is only 25 mA at no load. This makes them ideal for battery powered applications. The maximum power output of an SQ unit is 1 Watt.

The output voltage of the SQ power supply is directly proportional to the input voltage. The power supply will start with input voltage as low as 1 volt, and will not be damaged by inputs as high as 18 VDC. Each SQ supply has an internal bleeder on the output for safety. The value of the resistor is such that it dissipates less than 0.05 watt. The output ripple of each supply is typically less than 2% at full power. Each unit is encapsulated in a high thermal conductivity epoxy resin which eliminates problems associated with moisture.  All SQ power supplies are designed to withstand extremes of shock, vibration, acceleration, and thermal shock in accordance with MIL-STD-810.
The load regulation of an SQ power supply is approximately 20% from NO LOAD to FULL LOAD. To achieve accurate regulation, an external feedback loop may be utilized. The two output leads are floating and fully isolated from the two input leads by over 1 tOhm with less than 50 pF of coupling capacitance. This permits either positive or negative polarity operation. All SQ’s are reverse input voltage and short circuit protected.

The SQ Series high voltage power supplies are driven by an input voltage placed onto the input pins, of any voltage between 0 to 12 VDC. There is NO internal connection between the input and output pins. As can be seen from the above, the output voltage is nearly linear with respect to input except near the lower input voltage region. Here, the output drops off rapidly as the input is lowered with the minimum input voltage needed for reliable starting being 1.0 VDC.

The maximum output current ability is achieved at full output voltage and must be derated linearly as the input voltage decreases. Therefore, a 1 kV 1 Watt unit, which is capable of providing 1 mA at 1 kV will only be able to provide 0.5 mA at 500 volts out indicating that the output power capability is parabolic with respect to output voltage. SC power supplies may be driven from a three terminal regulator, or run closed loop with a suitable regulation scheme.  The input capacitance is 10 uF AC bypass. Vout max is defined as the maximum output voltage of the power supply with the standard 12-V input.