Constant Current Constant Voltage Power Supply Schematic

Simple 5 amp regulated power supply circuit.

Constant current constant voltage power supply schematic.

I preferably want to use a op amp which will work on a single supply like a lm358. This circuit produces an output that may be equal to the input supply voltage but the current is well regulated and can never exceed the 5 amp mark. How does the power supply circuit work. Rs is the current sense resistor of the power stage used to generate a ramp for the current mode pulse width modulation pwm loop.

This power supply has following features. The lt3741 simplifies the design of constant current constant voltage regulators by combining an accurate current regulator and an accurate voltage regulator in a single ic thus eliminating power system design trade offs. Voltage causes a current not the other way around so to make a device that provides a constant current no matter the load we have to use negative feedback and convert the current flowing through our load into a voltage. Hi i m trying to build an adjustable constant current constant voltage power supply using a lm2576.

I need to adjust the voltage to approximately 24v and then set the current limit between 0 and about 4a. As you can see the cm pin enables you to omit the series power dissipative current sense resistor at the output. R1 is precisely selected so as to maintain a safe 5 amp maximum current limit that can be withdrawn from the circuit. I easily get continuously adjustable output voltage 1 30v and current 0 6a which is pretty enough for circuit testing and other things i m also using 7805 voltage regulator ic for 5v constant voltage and current.

A cmos op amp number icl 7611 controls the input current through a p channel hexfet power transistor no. The advantage of this outline are. The above circuit is for testing only. As is the current sense amplifier gain of the lm5117 which has a typical value of as 10.

As they are connected in a serial form so use the together current by i vref r1 while the vref to be defined by the ic2 is 1 25v. A constant current source ccs in electronics is a device circuit that produces a constant value of current regardless of source voltage or load resistance. The lt3741 is a synchronous buck dc dc controller designed to regulate output currents up to 20a and output voltages up to 34v with a current regulation accuracy of 6 and a voltage accuracy of 1 5. In this circuit we use a lm317 to control a mj2955 15 amp pnp transistor.

If the load draws current at 1 a the supply will automatically switch to cc mode. A constant current circuit can also be used as a current limiter. Input voltage 12v dc. For example suppose the power supply is set to 5 v and current limit is set to 1 a.