1.3 - 32 V / 5A Power Supply w/ Short Circuit Protection by LM338

Description:

This is a LM338 based power supply which is not complicated and easy to build. I am using the supply for a long time, have no problem yet. Only current adjust is missing but I overcome this situation by using an LCD panel ampermeter. There is no PCB for the circuit. I took a 3x16 copper plate and strip the unused areas by a knife. If you want you can use analog meters instead of LCD panels.

Notes: 

1. Use thick wires for connections.
2. When connecting the LM338 to the heatsink use thermal paste. 
3. Use external supplies for LCD panels. They can be 9V batteries. The panels I use draws 1mA current and the batteries last sufficiently long time. If you have small transformers which can supply regulated 9V, you can use them. You need separate transformers for each panel!
4. The transformer should be 100 Watt but if you don't need high current you can try transformers that you already have. (I can draw 6A from 100Watt transformer.)
5. If you have multi winding transformer you can use the diode connections shown in schematic. Diodes must be 10-15 A.
6. Be careful while connecting LM338. Don't put it inverse.
7. Output of your transformer mustn't exceed 25V AC...

Electronic Fuse for DC Short Circuit Protection by BRX46

Description:

This is an electronic fuse that protects the load against short circuit. Relays must be chosen with a voltage value equals to the input voltage. Don't omit using the 100uF capacitor with appropriate voltage value with respect to the input voltage. If you can't provide, you can use C106 instead of BRX46.

You can adjust the current with using 10K potentiometer. If you will use the fuse with very high currents, lower the 0R6 5W resistor value (ex. 0R47, 0R33, 0R22 or 0R1). Watt value of the resistor should be increased also. 

You can download ARES PCB layout file of the circuit from here .

Symmetric Power Supply for Op-Amp Applications by 78xx and 79xx

Description:

This is a symmetric supply that can be used to power operational amplifier used circuits. You should be careful during using this power supply since it has no short circuit protection. On the other hand you can connect appropriate diodes to protect the circuit.

78xx and 79xx series regulators are used. xx denotes which voltage value is required at the output and xx value must be same for both ICs. J1,J2 and J3 are the transformeroutput connections. J2 must be connected to the middle output of the transformer...