Voltage Doubler with NE555 timer chip

This circuit is used to drives relays of 24 and 18 VDC from a 12 Volt power supply. The basic circuit on the IC NE 555 timer and use this circuit with almost any NPN or PNP power transistor.

Parts:

Resistor
R1 = 47K
R2 = 10K
R3 = 56R

Capacitor
C1 = 0.01uF
C2 = 0.01uF
C3 = 0.001uF
C4 = 0.1uF
C5 = 50uF

Transistor
Q1 = TIP29 , TIP120, 2N4922, TIP61, TIP110, or 2N4921
Q2 = TIP30 , TIP125, 2N4919, TIP62, TIP115, or 2N4918

IC
U1 = NE555

Comments

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