This is the schematic diagram of DC motor speed controller circuit. The circuit applies two oscillators/timers which are connected as a Pulse Width Modulator (PWM). The timer chip which applied in this circuit will be an nmos dual timer/oscillator NE556. This timer IC has two 555 timers in a single 14-pin IC package.
This diagram is certainly the 6 transistor Tilden H-bridge circuit; while not as old as the original “basic H-bridge,” this goes “way back,” and will be the basis for a lot of BEAM driver circuits. Bruce Robinson explaination about this circuit: I did a few revised drawings for Ian quite a while back, so he could place them up at beam-online. However, they did not get posted inside the midst [...]
The above diagram is the schematic diagram of an electronic motor starter circuit. This motor starter protects singlephase motors against voltage fluctuations and overloading. Its salient function is a soft on/off electronic switch for simple operation. The transformer steps down the AC voltage from 230V to 15V. Diodes D1 and D2 rectify the AC voltage to DC. The unregulated power supply is given towards the protection circuit. Inside the protection [...]
This is a DC motor controller circuit, built using transistor TIP31 based on H-Bridge concept. The switch S1 and S2 are normally open , push to close, press button switches. The LED function is to indicate the direction of motor rotation, you may use any common LED type. The TIP31 transistors capable to handle 3A maximum electric current, you may change the transistors for DC motors with higher current consumption. [...]