For High voltage and High current circuits we need dedicated High power voltage Regulators, here we designed 5 Volt 5 amp Voltage Regulator to give Regulated output voltage at 5 Ampere output current. In this circuit we have used IC LM338 5 amp Adjustable Regulator from texas instruments.
LM338 is a three terminal positive voltage regulator with capability of delivering 5 Amps current over 1.2 V to 32 V output range. It requires only two External Resistors to decide the output voltage and it will provide good load and line regulation.
- IC LM338
- Capacitor 0.1µF, 1µF (ceramic) each one
- Resistor 270Ω
- Variable Resistor 1KΩ
IC LM338 Package and Pin details
Circuit Construction & Working
The IC LM338 comes in two different package and we can choose depends on out circuit design. LM338 has three terminals names as pin 1 Adjustment, pin 2 Output and pin 3 Input. This IC provides better thermal overload protection and current limit constant with temperature. It is best suitable for Battery charger circuit, Constant current power supply and Adjustable Regulator circuits.
In this circuit Capacitors C1 and C2 are Ceramic capacitors and it is here for to provide filter function to the input supply and output supply. Here Voltage divider setup is made by R1 and R2 Resistors, Variable R2 Resistor Value decides the output voltage Range from LM338. Use heat sink over the LM338 for better operation. Refer data sheet for more information on thermal and voltage Regulation calculations.