I have connected LM317 voltage regulator to get variable voltage as per the circuit in the datasheet. Input voltage is 24V from a power supply. However, the output voltage is 24V which does not vary even if R2 is varied. I have checked all connections, added decoupling caps to input and output, tried replacing R1 and R2, replaced LM317, replaced the breadboard; but I still cannot get output voltage to vary !!
I read online that LM317 needs a minimum load current to work properly, so I added a LED with 330 ohm resistor at the output. The LED turned on, but it received 24V and the resistor became hot very quickly.
This should be an extremely simple thing but I am stuck as to why it does not work ! I have R1=250 ohm and R2 is 1K trimpot which I have set at 750 ohm, so I should get 5 V as output, but I end up getting 24V.
I read online that LM317 needs a minimum load current to work properly, so I added a LED with 330 ohm resistor at the output. The LED turned on, but it received 24V and the resistor became hot very quickly.
This should be an extremely simple thing but I am stuck as to why it does not work ! I have R1=250 ohm and R2 is 1K trimpot which I have set at 750 ohm, so I should get 5 V as output, but I end up getting 24V.