What Must todo

Low power inverter schematic are only use 9 components , one of which IC 556 , TIP120 NPN Darlington transistor.And turns 10 to 16 Vdc into 60 HZ, output 115 V square-wave power to operate ac equipment up to 25 W. In the circuit first ic originally hires as a timer chip m for stabilizatiom oscilator with components R1 and C1 setting frequency oscilator. Then the two transistor driver, drive the transformer push-pull fashion, When one transistor is biased on , the other circuit cut-off . The transformer is a 120V/18Vct unit that is connected backwards, so that it steps the voltage up rather than down. Oscilator circuit operates from about 4 to 16 V for  stable output.

 Part List :
R1 = 1K
R2 = 12K
R3 = 1K
R4 = 1/4W
C1 = 1uF
IC = 556
Q1 = TIP120
Q2 = TIP120
T1 = 120V 18VCT

By using the circuit you do not bother to roll  up a transformer that is used to reduce voltage AC 220V to 7V ,9 V or 12V, etc. When using a large transformer we will find it hard to make transformator. by rolling hundreds or even thousands of times roll. But if you use this circuit a little just enough to roll trafo not to small, and its be relatively small.

This circuit operating with IC uA723 and add amplified with transistor  TIP31 or similiar transistor with TIP31 . Input voltage for circuit about 10 - 40 volt DC , formerly of AC voltage 220 volts or 110 volts , then lowered by the transformer voltage to 30 volts. And the supply output voltage from 1 volt to 35 volt DC  you can adjust it on potentiometer  R2.
 See this circuit power supply below :

Output voltage transformer used 10 to 40 Volts . On resistor Rsc is the current limit set resistor. Its value is calculated as :

Rsc = 0.65 Volt

For Example : If you need current output 2.0 A

Rsc = 0.65 / 2.0 = 0.32 Ohm

So , you must use 0.32 Ohm to current output 2.0 A

The circuit charger is equipped with voltage output settings , so that we can regulate how much voltage to charge the battery. And the settings using the potentio making it easier for us managing voltage up to a mV. See charger circuit below :

The Schematic above shows a 10A power suplly with a 5V output and with power 50W. It is a flyback converter operating in the continuous mode. The circuit features a primary side and secondary side controller with full protection from fault conditions such as overcurrent. After the fault condition has been removed the power supply will enter the soft start cycle before recomming normal operation.

IC TL494 switching regulator IC provides pulse-with modulation control and drive signals for the power supply , The upper MOSFET , Q7 , in the power switch stage is driven by a simple transformer drive circuit. The lower MOSFET , Q6 , since it ground referenced , is directly driven from the control IC.