Description. Here is the circuit diagram of a simple soft start power supply using the well known voltage regulator IC LM317.Here the IC is wired in soft start mode in which the output of the IC gradually increases to the desired output voltage .When the input voltage is given to the IC , the capacitor […]
Description. Here is the circuit diagram of a powerful 12V regulator that can deliver up to 15 A of current.The common voltage regulator IC 7812(IC1) is used to keep the voltage at steady 12V and three TIP 2599 power transistors in parallel are wired in series pass mode to boost the output current. The 7812
Description. Here is very simple circuit in which the LED becomes ON only after a preset time the power supply is switched ON. When the power supply is switched on the transistor will be OFF. The capacitor now charges via the preset R3 and when the voltage across C1 is sufficient, the transistor switches ON
Description. For circuits using TTL ICs the supply voltage is a great concern and a slight increase in supply from the rated 5V may damage the IC. Using fuses alone does not solve the problem because a fuse may take several milliseconds to blow off and that’s enough time for the IC to get damaged.
Description. Here is the circuit diagram of an adjustable voltage regulator using IC L200. L200 is a monolithic integrated adjustable voltage regulator IC having features like current limiting, thermal shut down, power limiting, input over voltage protection etc. Here the regulator is designed to produce an output adjustable between 2.85V to 15V at 1A.The resistors
Description. Here is a simple scheme for adding a blown fuse indicator to your existing power supply circuit. This is done by just adding a resistor and LED to the existing circuit. The LED and resistor are connected in series and this combination is connected in parallel to the existing fuse. When the fuse is
Description. This is a simple approach to obtain a 12V and 5V DC power supply using a single circuit. The circuit uses two ICs 7812(IC1) and 7805 (IC2) for obtaining the required voltages. The AC mains voltage will be stepped down by the transformer T1, rectified by bridge B1 and filtered by capacitor C1 to
Description. The circuit given below shows a negative reference voltage supply.The reference voltage can be set to precise values by R2. The circuit operates in the same manner as the positive reference voltage supply circuit shown previously.The circuit is nothing but an inverting DC amplifier based on IC uA741.The circuit operates on a negative power
Description. The circuit given below is a variable positive voltage reference supply.The reference voltage can be set to precise values by R2.Basically the circuit is a DC amplifier based on op-amp uA 741.The negative feedback is given via the zener diode. Circuit diagram with Parts list. Notes. Assemble the circuit on a good quality PCb
Description. A simple circuit for converting a floating dual power supply is shown here.The circuit is based on a uA 741 op-amp. The input supply is splitted by the voltage divider circuit formed of R1 & R2 ,and given to the non-inverting input of the IC1. The output (Pin 6) is connected to the inverting
Description. This voltage regulator circuit can deliver up to 3A at 12V output voltage. The circuit can be employed on occasions when a current of more that 3A is demanded for regulator. IC regulators of such high current rating are pretty hard to find. The transformer T1 steps down mains voltage, to 12rms & the
Description. Commercially available voltage regulator IC’s can deliver up to 1A output current. For example 78xx series regulators are available in different voltage ratings, but in any case the current should not exceed 1A. The transistor Q1 (2N 29055) used here has 5A current capacity. The resistor R1 is used to keep the current through
Description. Here is a simple circuit for boosting 12 V DC to 24 V DC .The circuit is designed straight forward and uses few components.With few modifications the circuit can be used to boost any voltages. The transistor Q1 and Q2 (D1616) essentially drives the primary of the transformer.The diodes rectifies the output of transformer
 Description. Here is a simple mains power failure alarm/detector circuit that produces an alarm whenever the mains supply fails. Lot of such circuits are available, but the peculiarity of this circuit is that it requires no back up power source like a battery to power the alarm when the mains is absent. When there is
Description. This straight forward circuit will protect electrical appliances from over voltage as well as under voltage. The circuit also produces an alarm when the power supply comes back. An ideal circuit for home to protect your valuable equipments from voltage fluctuations. The same circuit with some modifications can be used to make a automatic
Description. Here is the circuit diagram of 9 V regulator using popular 7809 IC. The 7809 is a 9 Volt voltage regulator IC with features such as internal current limit, safe area protection, thermal protection etc. A 16 V transformer brings down the 230V mains, 1A bridge rectifier rectifies it and capacitor C1 filters it
Description. 7805 is a 5V fixed three terminal positive voltage regulator IC. The IC has features such as safe operating area protection, thermal shut down, internal current limiting which makes the IC very rugged. Output currents up to 1A can be drawn from the IC provided that there is a proper heat sink. A 9V
Transformerless power supply Circuit Description Here is a low cost and simple circuit that can be used to power up small electronics devices. The power is directly tapped from the mains via resistor R1. D1 rectifies the voltage and C1 and C2 are used to filter the output. The zener diode D2 will regulate the
6 Volt Regulator using IC 7806 Description Here is the elementary 6V 1A power supply circuit using 7806 IC. The 7806 three-terminal positive voltage regulator is available in the TO-220/D-PAK package making them useful in a wide range of applications. 7806Â employs internal current limiting, thermal shut down and safe operating area protection, making it
Power Supply Circuit-40 Volts-2A LM317 is a widely used linear voltage regulator. It has 3 pins; input, output and adjustment. LM317 are energy wasters and always require a heat sink to keep the temperature of the circuit low. But due to its simplicity LM317 find a place in a wide range of power supply units.
Dual Adjustable Power Supply Circuit A power supply is a circuit based electronic device that supplies the needed electrical energy to an electrical load. Power supplies can also be named as electric power converters as they are used to convert electrical energy from one form to another. Power supplies are used in everyday consumer devices
Adjustable/Variable Voltage Regulator using LM 117 IC A circuit that regulates the output voltage within a desired range and can be adjustable within that range is called an Adjustable Voltage Regulator. Depending on the range of voltage to be adjusted, there are many types of adjustable voltage regulators. Two of the most commonly used IC’s
