Pulse Width Modulators using LM339

The first example uses the standard op-amp oscillator circuit to generate a triangular waveform which is level-shifted and fed to a comparator (e.g. LM339) to give the PWM waveform. Most people will want to use two comparators rather than one op-amp and one comparator so that is what we show here.
Read More Source:http://www.4qdtec.com/pwmmod.html

555 timer pulse generator
To drive ignition coils is to use a 555 timer pulse generator. A 555 generates a square wave output that triggers the 2N3055. Adjusting the two potentiometers and the value of the capacitor will change the frequency of the output. Read More Source: http://www.geocities.com/mistertippy/sc ...
Bargraph Voltage Indicator by LM339
The circuit Bargraph Voltage Indicator used IC op-amp two quad voltage comparators to illuminate a series of 4 LEDs indicating volume level. The op-amp used in this particular circuit is the LM339. It is a popular IC and should be available from many parts stores. The 1K resistors in the ...
4 Level - voltage Detector by LM339
This circuit can sequentially indicate 4 separate voltage levels. The voltages are determined by the values of resistors R1 through R5 arranged in a simple voltage divider circuit. Source : http://home.cogeco.ca/~rpaisley4/Comparators.html Related Links LM339 comparator ic DC vol ...
Basic Memory Functions by LM339
Comparators can be made to perform a basic memory function by wiring them as a 'SET / RESET' type of FLIP/FLOP. This type of circuit can be used in unplugable walk around throttles to remember the direction of the train when the controller is disconnected. In the next diagram the comparator ...
Pulse Generator by IC LM350T and 555
This be Power Pulse Generator Circuit , by use the integrated circuit NE555 be Square wave Oscillator Generator. Fine the frequency done to a turn R1. From that time send output go to still transistor 2N2222 control give IC LM350T work have voltage come out the character pulse ...