Adjustable 1.5A linear regulator in TO-220-3
The LM317T/LF01 is a positive adjustable linear regulator from Texas Instruments, delivering up to 1.5A continuous output current. Output voltage is set by two external resistors from 1.25V up to 37V. The 64dB PSRR at 120Hz means it rejects rectifier ripple well enough for sensitive analog rails — think op-amp supplies or audio preamp stages. Built-in protection covers over-current, over-temperature, and short-circuit events — no external clamp diodes needed for most bench supplies or breadboard projects.
Sizing the output for your rail
The 1.5A output is continuous, not peak — derate for ambient temperature above 25°C per the datasheet's SOA curve. Quiescent current is 10 mA, which matters for battery-powered designs where every milliamp counts. Input voltage ceiling is 37V; the dropout voltage is typically 2V at 1.5A, so budget headroom. The TO-220-3 package with a tab can dissipate several watts with a heatsink — plan the thermal path early.