Presented here is a simple circuit “9V DC to plus/minus 5V DC converter” that can convert a 9V battery to plus/minus 5V DC supply using LM7805 and ICL 7660.
The operational amplifier requires a dual polarity power supply (+Ve and -Ve) because it has to swing on the output i.e. it does not swing into action during the negative cycle of signal if the negative source is not given. Thus, for the proper operation, we need a dual polarity power supply.
Circuit Description of 9V DC to plus/minus 5V DC converter
While working with a battery, it becomes more difficult to get both +Ve and -Ve power supply. To overcome this difficulty, we have presented here a simple circuit “9V DC to plus/minus 5V DC converter” that can convert a 9V battery to plus/minus 5V DC supply.
The circuit of “9V DC to plus/minus 5V DC converter” is shown in figure 1, and is built around a very popular 5-volt voltage regulator IC LM7805 (IC1), CMOS Voltage converter IC ICL7660 (IC2) with few other components. The output of the battery (9V) is given to the input terminal (pin 1) of IC1, which converts it into a regulated +5V DC supply. The output from pin 3 of IC1 (+5V) is given to the V+ pin (pin 8) of voltage converter IC (IC2). Capacitors C3 and C4 including IC2 (ICL 7660) form a voltage converter section that converts +5V to -5V. The output -5V is taken from the Vout pin (pin 5) of IC2.
Click here to download PCB design for 9V DC to +/- 5V DC converter.
PARTS LIST OF 9V DC TO PLUS/MINUS 5V DC CONVERTER.
Capacitors |
| C1 = 470 µF, 25V (Electrolytic Capacitor)
C2 = 2.2 µF, 16V (Electrolytic Capacitor) C3, C4 = 10 µF, 16V (Electrolytic Capacitor) |
Semiconductors |
| IC1 = LM7805 (+5V series fixed voltage regulator)
IC2 = ICL 7660 (voltage converter IC) |
| 9V battery
Connector |