NE555芯片组成的6V转12V，3A电源电路图
This 6V to 12V dc-dc boost converter can drive a load in 12V about 3A current.The 555 timer IC is operated in astable mode, generates about 29Khz frequency of about 54% duty cycle drives the input of TIP41C transistor.1000uF capacitor smoothens the output voltage of the dc-dc converter.LED and 1.5Kohm resistor serves as indicator and load for output stability when no load is connected.You can add a 12V zener diode (1N5242B)across output to ground for further output stability.
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