The circuit is a boost step-up regulator based around an LM2577-ADJ voltage regulator chip and a few other discrete components. Resistors R1 and R2 set the regulated output voltage.
A switch inside the voltage regulator closes between pins 4 and 3, causing current to flow through the inductor to ground. When the switch is released a few microseconds later, a back-EMF ‘kick’ is produced by the inductor, resulting in a positive pulse with respect to the input voltage. This pulse charges the output capacitor via the schotky diode, which tends towards an equilibrium voltage.
The switch continues to oscillate, the diode preventing the switch from shorting the output capacitor during the ‘on’ phase. The output voltage is monitored via the voltage divider R1/R2, causing the duty cycle of the switch oscillator to be continuously regulated in order to maintain a constant output voltage under varying loads.
The output voltage defined by R1/R2, if you want to take a 12 volt to 15 volt dc booster is easily.
- All circuits of LM2577
- Step up voltage converter
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- 5VDC to +12V and -12V Isolated dual power supply
- LM2577 5V to 12V DC Converter step up Voltage Regulator
- ICL7660 DC to DC Converter input 5V to output +/-5V
- 6V to 12V Converter by transistor
You can buy the circuit module that easy to use at amazon.com.
LM2577T-12/NOPB – IC, STEP-UP VOLTAGE REGULATOR
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