LM317T Voltage Regulator with Pass Transistor

Switched mode power sources (SMPS) - a modern power supply with high efficiency. The traditional linear power supply with a consistent regulatory elements remain constant output voltage when changing the input voltage or load current due to change of its resistance. Linear Regulator (stabilizer) so it can be very inefficient. Switched mode power sources use high-frequency switch (transistor) with variables on / off states, to stabilize the output voltage. Ripple output voltage is caused by the key mode, filtered by LC filter.



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