Here is the USB printer switch circuit design with two USB input ports and one USB output port. This a really simple device that allow two computers (desktop/laptop) to select a single USB printer or some other USB device, such as an external flash drive, memory card reader or scanner. A rotary switch selects the… Read More »
This is a really simple smoke alarm circuit design. The circuit consists of two important modules that are sensor module using a photo interrupter module and alarm module using a tone generator IC NE555 with astable multivibrator configuration and then connected to the speaker, so you can hear the alarm sound.
This is the digital fan speed control circuit design that can be utilize to control the speed of 220V fans using induction motor. The speed control is nonlinear, i.e. in steps. The current step number is displayed on a 7-segment display. Speed can be varied over a wide range because the circuit can alter the… Read More »
Here is the 250W RMS power amplifier circuit called Legend-Stage Master. This is the previous version of Legend-Stage Master MK2. The circuit is based on power MOSFET and give a great output performance for indoor audio sound system.
This is the circuit design of unipolar stepper motor driver to control unipolar stepper motors with 5, 6 or 8 wires. It uses four MOSFET IRFZ44. This circuit can be operated in free-standing or PC-controlled mode.
This is a low cost, simple, yet a surprisingly powerful electronic siren powered by just a 9V battery. The circuit may provide the final circuit block module in an alarm circuit using a relay to activate it.
Unipolar Stepper Motor Driver Kit — CK1405 Unipolar Stepper Motor Driver Kit. Standard circuit to driver unipolar stepper motors with 5, 6 or 8 wires. Uses 4 IRFZ44’s. Can be operated in free-standing or PC-controlled mode. Uses standard IC’s: 4013, 4030 and 4093.
This bipolar stepper motor driver circuit will drive a bipolar stepper motor using externally supplied 5V levels for stepping and direction. These usually come from software running in a computer or from a microcontroller unit. The circuit uses IRFZ44 and MTP2955 MOSFET’s.
Equaliser circuits typically divide the audio spectrum into separate frequency bands and have independent gain control for each band. The output of each band is mixed at IC4(A) and then fed to an audio power amplifier. Proper quality factor (Q) needs to be selected to avoid overlap in adjacent bands as this introduce colouration into… Read More »