Adjustable Low-voltage Power Supply

If you want to check the behaviour of an electronic circuit at low voltages, an adjustable power supply as shown here may be helpful. Powered from a 3 to 16 volts source (DC for sure), it will provide a stable output voltage in the 0 to 1.5 V range.

Adjustable Low-voltage Power Supply Circuit Diagram

Power Supply Circuit Diagram

Multiturn trimpot P1 allows the output volt-age to be adjusted with good precision. The BC337-400 output transistor raises the out-put current to about 200 mA bearing in mind that the minimum supply voltage is 3.5 V. The transistor’s dissipation should be taken into account, and a more power ful t ype used if necessary.

T1 may be omitted and R2 replaced with a wire link if you are happy with 3 mA at 3 volts out, 10 mA at 6 V or 20-30 mA at 10-16 V.

These values represent the maximum output current of the TLC271 op amp. Without T1, the minimum supply voltage is 3.0 V.

Author:Vladimir Mitrovic - Copyright: Elektor