Free electronic circuit design and schematic diagram
Thermoelectric cooler (TEC) or Peltier cooler is becoming popular because of its robustness and maintenance free characteristic. Here is one example of a linear thermoelectric cooler (TEC) driver circuit. This driver is capable of delivering ±2A into a TEC. This circuit operates on a single +5V supply and drives the TEC in the most preferred “constant-current” mode. Here is the […]
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This SMPS AC-DC converter gives good efficiency. Test data shows efficiency of 83.2% at 115 Vac input and 6A output current, and 85.4% at 230 Vac input and 6A output current. Moreover, the input voltage range is universal, accommodating 92 to 276 Vac variation with only 24 mV change in the output voltage. Here is the schematic diagram of the […]
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More efficient lead acid battery charger can be implemented using switch mode circuit. A switch mode for lead acid battery charger can be constructed using bq24105 battery charger controller. The bq24105 was originally designed to charge single-, two- or three-cell Li-ion and Li-polymer battery packs. Its features doesn’t include the control for lead acid battery charger termination. Here we add […]
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This power factor controller accept voltage from 90 to 268 Vac, that’s why we call it power factor controller with universal input, since any standards of mains supply in almost any country would fall within that range. This power factor controller is capable of handling up to 450W load. Here is the schematic diagram of the power factor controller circuit: […]
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This constant current constant voltage SMPS can be used to efficiently charge a battery. This circuit gives 7.2V at constant voltage mode, and 600 mA at constant current mode. Here is the schematic diagram of the circuit: The mechanism is simple, when the load impedance is high, then the output voltage will be constant at 7.2V. When the load impedance […]
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High voltage current sensing/monitoring can be designed using LTC6101 op-amp. The following current sensing circuit is capable of measuring electrical current in 500 volts system. Here is the schematic diagram of the circuit: Two external Mosfets is added to hold off the voltage, allows the LTC6101 to be connected to a very high potentials and measure the current flow. The […]
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Active power factor correction stabilize the electrical demand of a device to give the best power factor characteristic of many types of loads. To meet power factor regulation, a low cost solution should be designed. In many application, the need of high DC voltage is usually implemented by a direct rectification of the AC line followed by bulk capacitor filtering. […]
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