The circuit is used to control the bank of LEDs using PWM, my problem is the value of R3 is wrong, now I used 10M ohm and it started switching on and off bt the LEDs dont shine bright which means the 2n2222A do nt saturates.PLz click the circuit is on the link below.



Reduce or eliminate R7, it is completely unnecessary and is limiting the LED current as well as the base current, which makes your transistor not fully turn on.

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    \$\begingroup\$ R9 and R10 can be eliminated as well. 3 LED's in series takes about 9 volts to turn them on at a minimum level, or 3.0 volts per LED. At 3.5 volts per LED (10.5 volts) they will be at maximum brightness. Just use the 220 ohm resistors. They will run at about 14mA each. Plenty safe and plenty bright. \$\endgroup\$ – Sparky256 May 8 '16 at 3:11

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