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