Uninterruptible Power Supply with PIC17C43 Microcontroller

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 »

Variable / Adjustable DC Power Supply 1.2V – 25V using LM338K

This is variable DC power supply circuit, or we can call it adjustable DC power supply which give us a 1.2V-25V output voltage. The power supply schematic above is taken from the datasheet of regulator LM338K manufactured National Semiconductor. The circuit uses IC LM338K as the voltage regulator, so we will get the stable and… Read More »

1 – 9V Variable Desktop Power Supply

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 »

0-24VDC Digital PIC Power Supply

This is 0-24VDC digital PIC power supply circuit. This variable power supply controlled with PIC microcontroller. There is LCD display in this circuit which will show the actual value of power supply output. This power supply use push on switch to adjust the output voltage and current value. Schematic Diagram: Component List: C1 = 2000uF… Read More »

6-12V Variable Regulated Power Supply

This is an adjustable / variable power supply which have adjustabled output voltage from 6-12 DC volt. This power supply can be used for general circuit or gadget which require 6 – 12DC voltage to work. Component Parts List: T1 = primary 115[220]/secondary 8 VAC transformer. Center Tap not needed. Q1 = 2N1613, NTE128, or… Read More »

Hobby Power Supply

Hobby power supply for electronic hobbysts. This is power supply circuit which have 2 output that are static output and adjustabled output. The static output is stabled and regulated output. The circuit is based around the 7805 voltage regulator. It has only 3 connections (input, output and ground) and it provides a fixed output. The… Read More »

35W Tube Power Amplifier with EL34

This is the circuit diagram of 35W Tube Power Amplifier with EL34. This tube amplifier designed in 1953 and worked from 1954 until 1989. If you’re interested with classic circuit and classic components, then you should try this circuit. The circuit is interesting but i think it is hard to find the tubes. Schematic Diagram: