Free electronic circuit design and schematic diagram
If only a 5 volt positive supply is available and you need a negative voltage for op-amp or other biasing purpose, the you can generate the negative supply from the positive supply using this circuit. This circuit give same functionality with our previous 555 switching circuit, but now we use a CMOS inverter gate. Using CMOS component allow our circuit […]
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The circuit below is the basic for standard symmetrical power supply. If your circuit need high current then this circuit is suitable. Here you can see the circuit’s schematic diagram. You need a center-tapped transformer to build this symmetric power supply. This power supply circuit is widely used in op-amp application, as well as in high-rated power amplifier. If you […]
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This simple Batteries charger circuit is designed for NiMH/NiCd batteries. It need no micro-controller nor any programming. Linear Technology Corporation produce the LTC4060, an autonomous 1- to 4-cell, 0.4A to 2A linear NiMH and NiCd battery charger complete controller. Here are the main features: No Sense Resistor or Blocking Diode Required Complete Fast Charger Controller for Single, 2-, 3- or […]
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If you need a negative supply for op-amp or just need negative bias voltage while operating from a single supply voltage (for battery operation for example), this circuit helps providing the negative supply for you. The circuit is based on charge pump driven by 555 switching circuit. Here is the schematic diagram: The negative voltage produced by this circuit is […]
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This circuit provide automatic current limiting up to 8.4A. Unlike current limiter that uses only a resistor, this current limiting circuit doesn’t drop the voltage, or at least keep the voltage drop at minimum, until a certain current amount is exceeded. This current amount limit is adjustable from 1.4 A to 8.4A using a potentiometer. You can modify the component […]
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Basic interruptible Power Supply Circuit consist of regular power supply adapter and battery connection. This basic system is a “hot” battery connection, meaning that there is no switching mechanism in connecting and disconnecting the battery, the battery is always connected! This hot connection is very simple to implement and very robust because there would be no switching delay, the output […]
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The first thing you must have in your workshop/lab is power supply. In experimenting many new electronic circuit design, it is easier if you have a flexible adjustable power supply. Here is an adjustable 0-30 volts power supply design. The circuit schematic diagram is shown below. The core of the circuit is 723 voltage regulator integrated circuit. A Darlington pair […]
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