This is a simple design for inverter that produces voltage. This circuit is a good solution to the 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. This is the figure of the circuit.

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. A zener diode may also be used to regulate the output voltage. For better regulation, a 79LOxx series regulator can be used.

Part:

R1 24K 1/4 Watt Resistor

R2 56K 1/4 Watt Resistor

C1 3300pF 25V Ceramic Capacitor

C2 47uF 25V Electrolytic Capacitor

C3 10uF 25V Electrolytic Capacitor

C4 100uF 25V Electrolytic Capacitor

D1, D2 1N4148 Silicon Diode

U1 555 Timer

MISC Wire, Board

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. A zener diode may also be used to regulate the output voltage. For better regulation, a 79LOxx series regulator can be used.

Part:

R1 24K 1/4 Watt Resistor

R2 56K 1/4 Watt Resistor

C1 3300pF 25V Ceramic Capacitor

C2 47uF 25V Electrolytic Capacitor

C3 10uF 25V Electrolytic Capacitor

C4 100uF 25V Electrolytic Capacitor

D1, D2 1N4148 Silicon Diode

U1 555 Timer

MISC Wire, Board