This is a MicroChip Uninterruptible Power Supply (UPS) reference design with PIC17C43 microcontroller. The document is available to download from the end of this post. At times, power from a wall socket is neither clean nor uninterruptible. Many abnormalities such as blackouts, brownouts, spikes, surges, and noise can occur. Under the best conditions, power interruptions… Read More »
Here the variable desktop power supply which will convert a high input voltage (12V) from the SMPS / PSU of a desktop computer into small output voltage (1.25 to 9 volts). This converter will be very beneficial for electronics hobbyists. An adjustable three-pin voltage regulator chip LM317T (IC1) is applied right here to deliver the… Read More »
This is the circuit diagram of USB powered stereo computer speaker, or it widely known as multimedia speakers for PCs. The circuit has single-chipbased design, low-voltage electrical power supply, compatibility with USB power from computer, simple heat-sinking, inexpensive, large flexibility and wide temperature tolerance. At the heart of the circuit is IC TDA2822M. This IC… Read More »
Here is the schematic design of car cigar lighter to USB power port. Nowadays, almost all computer systems have logic blocks for working with a USB port. In practice, a USB port is capable of supplying more than 100 mA of continuous electric current at 5V to the peripherals which are hooked up with the… Read More »
This 300W OCL power amplifier -i’m sorry for the blur diagram, but it should be readable- use 4 pairs of 2N3055 dan MJ3055 transistor as the main power components. This is good circuit, i’ve built this OCL (ouput capacitor-less) power amplifier circuit for my school project, and of course i use it for my home… Read More »
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 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 easy built and very low-cost circuit purposed to protect your electronic appliances / devices, such as Personal Computer, TV, recording devices, refrigerator, and other devices during sudden tripping and resumption of home mains supply. Appliances like refrigerators and air-conditioners are more inclined to damage due to such conditions.
Here the notebook anti theft protector circuit to secure your important netbook / notebook from stealing. Basically, this is a mini security alarm generator. Fixed inside the notebook case, it will definitely sound a noisy alarm when a person attempts to grab the notebook. This very sensitive circuit utilizes a homemade tilt switch to turn… Read More »