Monday, July 6, 2009

Voltage Inverter

This simple 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, so it doesn't add much in the way of size and cost to a project.



Total Qty.
R1124K 1/4 Watt Resistor
R2156K 1/4 Watt Resistor
C113300pF 25V Ceramic Capacitor
C2147uF 25V Electrolytic Capacitor
C3110uF 25V Electrolytic Capacitor
C41100uF 25V Electrolytic Capacitor
D1, D221N4148 Silicon Diode
U11555 Timer
MISC1Wire, 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.
  1. For better regulation, a 79LOxx series regulator can be used.
  2. A zener diode may also be used to regualte the output voltage.
  3. Thanks to audioguru for correcting some errors in the original schematic. Read about it in this forum topic.


Post a Comment

555 Timer Circuit

Power Supply

Electronic Circuit Designer.