1.7k
Description
As you may recall the LM317 regulator is adjustable from 1.25 to about 35v. By adding 2 diodes you can drop the voltage slightly, about 0.6v of a voltage drop across each diode, so in the schematic below you can get close to 0v
Schematic
Parts List
QTY PART-REFS VALUE --- --------- ----- Resistors --------- 1 R1 220R Capacitors ---------- 2 C1,C3 100nF 1 C2 100uF 1 C4 10uF Integrated Circuits ------------------- 1 U1 LM317T Diodes ------ 2 D1,D2 1N4004 Miscellaneous ------------- 1 RV1 5k