The LM317 is an adjustable positive voltage regulator. Maximum output current, with adequate heatsinking is 1.5 A.
Recommended Operating Conditions
|VO||Output voltage||1.25 – 37||V|
|VI – VO||Input-to-output voltage differential||3 – 40||V|
|Tj||Operating junction temperature||0 – 125||°C|
|IO(MAX)||Maximum output current||1.5||A|
The output voltage is calculated as
The ADJ terminal current IADJ is typically 50 µA, while the reference voltage VREF is 1.25 V.
0V to 30V Regulator
The output voltage can be calculated as
High-Current Adjustable Regulator
Transistors Q1 and Q2 allow higher output currents. The output voltage is determined by the resistors R1 and R2.
Useful link: LM317 datasheet (pdf).