Voltage inverter circuit Diagram


Voltage inverter circuit Diagram

This voltage inverter circuit powering a dual supply op amp from a single battery problem. The circuit simply takes a positive voltage and inverts it.

It uses only one 555 timer and a few other passive components, so it doesn't add much in the way of size and cost to a project.

U1    1    555 Timer 
R2    1    56K 1/4 Watt Resistor 
R1    1    24K 1/4 Watt Resistor 
MISC    1    Wire, Board
D1, D2    2    1N4148 Silicon Diode 
C4    1    100uF 25V Electrolytic Capacitor 
C3    1    10uF 25V Electrolytic Capacitor 
C2    1    47uF 25V Electrolytic Capacitor 
C1    1    3300pF 25V Ceramic Capacitor

Circuit note:
V+ can be anywhere from 4 to 16V. -V is one volt less than V+. So for -12V output, use +13V input. The maximum current output of the circuit is about 280mA, more than enough for a few op amps. For better regulation, a 79LOxx series regulator can be used.

A zener diode may also be used to regualte the output voltage.