Using this circuit diagram can be built a very simple symmetrical power supply. This symmetrical power supply is very simple and is designed using the L165 chip. L165 chip can convert an asymmetric voltage of 6 + 40 V in a stabilized symmetric ± 3 V to ± 20 V.
C1 and C2 will be mounted as close as possible to the chip, and C4 and C5 will be soldered close to the output terminals. Because circuit can provide currents up to about 3 A, is essential to use a proper power wiring and the mounting of IC to a thermal radiator.
Using MAX641 integrated circuit, can be made a doubler voltage regulator. In this scheme high voltage electronic controller allows a maximum output current up to 1A. Low battery voltage detector input compare LB1 with internal reference of 1.31 V. LBO output goes in low state when the voltage at pin 1 falls below 1.31 V. The threshold voltage for "low battery", is determined by voltage divider R1-R2.
LED D1 illuminates the LBO output when the input voltage falls below 2.62 V.
Input voltage must remain below 5 V. The maximum effectiveness is 80% conversion.
Using MAX680 integrated circuit can be designed a symmetrical voltage doubler using few electronic components. The voltage doubler can be used in digital equipment, if they are powered from a battery or power source of 5 V .. Output impedance of each line is symmetrical about 200 ohms and maximum current up to 10 mA.