Tuesday, September 1, 2009

7812&7912 12 Vdc Dual Power Supply Circuit

7812&7912  12 Vdc Dual Power Supply Circuit
12 Vdc Dual Power Supply circuit with IC 7812&7912

Voltage Regulators low power consumption IC 78W series used in our instrumentation is now so cheap they are an economical alternative to simple regulators NPN-stabilizers. In addition, they offer the benefits of better regulation, current limiting / short circuit protection to 1000 mA shunt and heat down if the electricity disperses too. Indeed, is not the only way for these drives can be damaged polarity is incorrect or excessive input voltage. Regulators Series 78W to kind of stay 8V input voltage of about 35V, while the type 24v withstand 40V. Of course, of course, that regulators will not work with such an important input differential output as it would lead to excessive power is dispersed. All controllers will deliver the 78W series 1000mA current maximum expected input differential voltage output of less than 7V. Otherwise, too diffuse power, thereby bringing the fire extinguished.
Two transformers were used to step voltage 230-250V AC input power. It manufactures power transformers 6-0-6V secondary terminals. This output is fed into the rectifier and filter capacitor. Filtered IC6 that served 3-pin voltage regulator that provides a regulated output + 5V. It is used to enable the DPM system. It also comes as the network voltage source temperature accuracy.
Other manufactures transformers with a capacity of 12-0-12V at its secondary terminals. The center was established as a fountain in the previous case. The other two secondary terminals are fed bridge rectifier constructed using diodes. Output recovered is filtered using a capacitor C5 and C6 for food and IC7 IC. In-8 IC7, which are 3-pin regulators provide output voltage of ± 8V. These two voltages are signal generator. TO-8V power source is applied to the temperature of the network, and the reference voltage. It is also necessary to +12 V and-12V supplies for the implementation of operational amplifiers. This can be easily done using a 12V zener diodes. The output of bridge rectifier is attached to the +12 V and-12V, respectively, using two zener diodes. In the zener output is fed to the terminals of the operational amplifier supply. For supply
for operational amplifiers must not be very effective in regulating + 12V, the use of Zener diodes be costly.
For the testing of electronic components voltage above 50 V is required. This can be achieved through quadruple the chain tension. It consists of four diodes and four electrolytic capacitors. Unreasonable Administration Secondary 12-0-12V is connected to quadruple string. Quadrupled output of the circuit is 68V to ground.