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Lithium-ion (Li-ion) Battery Charger with MAX1879

Above diagram is the circuit of Lithium-ion (Li-ion) battery charger which built based single chip MAX1879. This is the simple and low cost battery charger for single-cell Li+ battery that does not dissipate power (no heat. The MAX1879, in conjunction with the AC linear transformer adapter and a PMOS FET, allows safe and fast charging of a single Li+ cell. The MAX1879 is not only an inductorless required solution, but also the lowest power dissipated solution among single-cell Li+ battery chargers.

Solid State Tesla Coil with 555 Timer

Here the circuit diagram of solid state tesla coil with 555 timer. Single transistor flyback driver induced a lot of complications on account of it really is operating principle. I received e-mails from those who had been unable to obtain it functional even after they are positive that their flyback and transistor is Okay. Moreover, because it is resonance frequency is determined by each individual a part of the method, any time you seek to draw an arc in the transformer, it alterations substantially in a lot of the circumstances. Simply because the operating frequency is vital for your security criteria, (each for mine and electrical power transistor's), I determined to generate it run on a continuous frequency and developed up yet another easy circuit, attempting to keep within the specified limits in the 555 timer.

Simple Power Supply Circuit for Laser

This is a very simple high voltage power supply circuit for laser device. It is low cost circuit and very easy to built. This power supply can be built with common parts, most of which you probably already have in your junk box. The secret of this circuit is the transformer used. It is a common 9V 1A transformer unit, connected backwards for step up. Please note that some people may have trouble with this supply. This is due to the slight difference in transformers. 

Regulated Current Booster for Power Supply

This is the regulated current booster designed to increase the DC current of a power supply . Even though the 78xx series of voltage regulators are readily available with diverse current outputs, you could increase the obtainable current output with this circuit. A power transistor is utilized to provide additional current for the load the regulator, preserving a continuous voltage. Currents as much as 650mA will flow by way of the regulator, above this value along with the power transistor will start out to conduct, supplying the additional existing for the load. This needs to be on an sufficient heat sink as it is actually most likely to obtain rather hot. Suppose you use a 12V regulator, LM7812. The input voltage must be a number of volts greater to permit for voltage drops. Assume 20 Volts. Lets also assume that the load will draw 5 amps. The power dissipation within the transistor will likely be Vce * Ic or (20-12)*8 = 40 Watt. It may possibly preserve you warm within the Win...

Variable DC Power Supply 3-24V / 3A

This is the variable DC power supply circuit. This power supply has regulated output, can be adjusted from 3 to 25 volts and the current output is limited to 2 amps as shown, however it may possibly be improved up to 3 amps or more by applying a smaller current sense resistor (0.3 ohm). Voltage regulation is controlled by 1/2 of a 1558 or 1458 op-amp. The 1458 may be substituted in the circuit, but it is suggested the supply voltage to pin 8 be limited to 30 VDC, which can be achieved by adding a 6.2 volt zener or 5.1 K resistor in series with pin 8. The 2N3055 and 2N3053 transistors need to be attached on proper heatsinks and the current sense resistor must be rated at 3 watts minimum.

600V Power Supply for QRO HF Amplifiers

Here the schematic design diagram of 600V power supply for QRO HF amplifiers. Amateur Radio Transmitters working with valves such as 807 or1625 operates properly using a plate voltage in between 600V to 700 Volts. The circuit described below is actually a full wave voltage doubler. The output voltage is twice the input voltage. For 230V AC input the output is going to be close to 600 Volts. Resister R1 is applied to minimize the initial high voltage and high currents. Capacitor C1, C2, C3 along with coils L1 and L2 form input line filter. The capacitors C4 and C5 protects diodes from high voltage transients on the AC line as well as minimizes inter carrier hum modulation of the R.F picked up by the mains. Capacitors C6 and C7 gives sufficient filtering for the output DC Voltage.

DC Short Circuit Protection with Electronic Fuse

Here the diagram of electronic fuse circuit. This circuit will help to protect the load against short circuit for DC circuit application. Relays should be chosen with a voltage value equals to the input voltage. Do not omit making use of the 100uF capacitor with proper voltage value with respect to the input voltage. The circuit use Silicon Controlled Rectifier (SCR) BRX46 which is designed for control systems and sensing circuit applications. In case you cannot find this component, it is possible to use C106 as a substitute of BRX46.