Free electronic circuit design and schematic diagram
This circuit enables you to connect your camera with very long wire. The circuit is actually a video amplifiers. At the sender part, the amplifier is used to make a stronger signal. This stronger video signal then can be transmitted through the long cables. The signal is transmitted using balanced mode, where two wires are driven in the opposite phase. […]
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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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Integration is one of basic signal processing that can be done in analog domain. Using operational amplifier (op-amp), integration operation can be done with very simple circuit with very high accuracy. Here is the schematic diagram of an integrator circuit: The resistor R2 should have the same value with R1 since R2 is employed to minimize the offset error due […]
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Using MAX232 integrated circuit, you can build a TTL-to-RS232 level converter that totally comply with RS232 electrical specification. The IC generate the higher positive and negative voltage (+10 and -10 Volts) from TTL power supply (5V DC) using switched capacitor. The switching circuitry is provided inside the chip, so you need only few caps for external components. Here is the […]
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Using only transistors as the active components, we can build a simple and low cost TTL-to-RS232 level converter. It uses only two transistors as the active components. Here is the schematic diagram of the converter: You can use any small signal transistor for this RS232 converter circuit. You can see the collector of Q1 transistor is connected to TxD, and […]
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Many new computers now only has USB port, and this serial to USB adapter might be the only help for old devices that provides only RS232/COM Port. This serial adapter uses FT232 USB-RS232 converter IC from FTDI (Future Technology Devices International). The main features of this USB serial adapter chip are: 384 byte receive buffer / 128 byte transmit buffer […]
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RS485 interface gives some more benefits compared to RS232: simplicity and the robustness for long distance transfer. RS485 is simpler because it uses only two wire (or a single pair) to carry out the data in bidirectional manner, using RS232, we need 3 wires at minimum to carry the data bidirectionally. RS485 cable length can be as long as 1.2 […]
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