Lm317 Adjustable Voltage Regulator Circuit

In this project we are going to design a simple adjustable power supply circuit using an lm317 voltage regulator ic.

Lm317 adjustable voltage regulator circuit.

The lm317 device is an adjustable three terminal positive voltage regulator capable of supplying more than 1 5 a over an output voltage range of 1 25 v to 37 v. Adjust voltage in steps 3v 6v 9v 12v. Working of lm317 voltage regulator circuit. The lm337 is the negative complement to the lm317 which regulates voltages below a reference.

It was designed by bob pease who also worked for national semiconductor. A dc adjustable power supply is an integral part of any power supply unit used in electronic equipment. 10 1 25x 1 r2 240 r2 1680ω. The device features a typical line regulation of 0 01 and typical load regulation of 0 1.

This voltage regulator circuit is very simple. Using lm317 and 2n3055 so easy and cheap. Input voltage is fed to the pin3 v in of the ic and regulated output voltage is available from pin 2 v out of the ic. The lm317 is a popular adjustable positive linear voltage regulator it was designed by bob dobkin in 1976 while he worked at national semiconductor.

It can supply greater than 1 5 a at the output. A classic voltage regulator circuit using lm317 is shown above. Lm317 is a positive voltage regulator with an adjustable voltage range from 1 25 v to 37 v. The lm317 circuit is shown in the below figure is a t y pical configuration of the lm317 voltage regulator circuit diagram including the decoupling capacitors.

So this is how we calculate the r2 and output voltage for lm317 voltage regulator circuit. The capacitor c1 used for the filtering of dc input voltage and further fed to the vin pin of the lm317 voltage regulator ic. This lm317 calculator can be also be used for some other ics like lm338 or lm350. It serves as an interface between a wall outlet and common power electronic equipment.

In most of the applications due to irregular loads the output voltage produced has fluctuations in it which can lead to damaging loads. The adjustable pin is connected with the two external resistor and connected with the vout pin of the ic. 4 lead acid battery charger circuits see 4 lm317 lead acid battery charger circuits for 6v 12v and 24v battery. The device features a typical line regulation of 0 01 and typical load regulation of 0 1.

And in fine 1 25v to 20v. With automatic charging and full charged indicator using tl431. The lm317 device is an adjustable three terminal positive voltage regulator capable of supplying more than 1 5 a over an output voltage range of 1 25 v to 37 v. High quality 3a adjustable voltage regulator.

Resistor network comprising of r1 and r2 connected in association to the pin1 adj is used to set the output voltage. This lm317 circuit is capable to provide variable dc power supply with an output of 1a and can be adjusted up to 30v.