Free electronic circuit design and schematic diagram
There are some digital and analog that can be used for compensating a PT100 RTD nonlinearity. We can implemented the digital linearization by implementing the previous generic equation or by a lookup table. By implementing the previous generic equation we can calculate temperature values directly, based on the actual measured RTD resistance. A lookup table allows an application to convert […]
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In some temperature-sensing applications there are some problems caused by the placement of sensors on location where the potential is very different from that of the data-acquisition-system common. So the operating temperature sensor must be isolated from its data-acquisition system galvanically. And the power’s source for the sensor was isolated. This circuit is designed to solve that problem. It provides […]
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To know someone is lying or not we can use lie detector. This is a simple lie detector that can be made in minutes. It works to detect the someone who telling lie but it is not as sophisticated as the ones the professionals use. Here is the schematic diagram of this circuit: The skin resistance will go down when […]
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The transmitters that either working in FM or in AM is familiar. This is transmitters circuit that can transmit both FM and AM signal simultaneously at two different frequencies FM in 100Mhz and Am in 20 MHz. Here is the circuit: To transmit the FM signal, this circuit uses the 5th harmonics of the fundamental 20Mhz. So the range of […]
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This is a FM Transmitter circuit. This circuit uses logic gates. This transmitter circuit has a RF oscillator. This oscillator uses 10.7Mhz ceramic filter and inverter N2 to drive the parallel combination of N4 to N6 through N3. Here is the circuit: The output impedance will be low because these inverters are in parallel, so an aerial of 1/4h wavelength […]
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This is pressure sensor signal conditioning circuit. It is simple and inexpensive circuit because it has small geometry and simple pressure sensor. It just uses a single Operational Amplifier. This circuit obtain power from from 3-V battery. To work properly this circuit must work in 0 C to 50 C temperature range. Here is the schematic diagram : This simple […]
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To obtain an accurate pressure value, we must remove the offset errors. There are many basic circuit designs that is used to remove the offset errors. This circuit uses three method to remove the offsets errors, they are symmetrical offset trim, asymmetrical offset trim and amplifier gain adjustment. Here is the circuit: The differential sensor output must be zero V […]
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