Newbie to electronics working on my comprehension of the LM317. Please feel free to quote and correct me where I'm not accurate.
So, I often hear that the "capacitors" should be placed as close to the LM317 as possible. I'm assuming they mean a "decoupling capacitor". The rest of my assumptions will be based on the ceramic "coin" type of capacitor using the attached schematic. I'm also assuming that a decoupling capacitor is the capacitor that connects the Vin to GND before the LM317; see C1 in schematic. Some post also mention a second decoupling capacitor connecting Vout to GND; see C2 in schematic, and that it is; under some circumstances, optional. The second capacitor should also be larger due to load variance on Vout.
The intent of decoupling capacitors is prevent oscillation. Oscillation from my comprehension is the fluctuation of Voltage and Current. So, the result in it's use with an LM317 is to aid in providing steady or "smooth" voltage and current. How it does this is analogous with an overflow gutter for a pool. When the circuit is powered the capacitors charge to it's rating. When voltage fluctuates up the capacitors discharge the "extra" voltage/energy to GND. When the voltage fluctuates down the capacitors discharge it's "stored" voltage/energy to the line it's adjacent/tapped into; i.e. Vin or Vout.
When soldering the capacitors for the through-hole type, it's best to have leads as long as possible. Something to do with the lead attributing to capacitance.
Also in the schematic 1N4007 is what they refer to as a "Protection Diode". And it's purpose is to prevent some type of current backflow from going into Vout which would damage the LM317.
So, I often hear that the "capacitors" should be placed as close to the LM317 as possible. I'm assuming they mean a "decoupling capacitor". The rest of my assumptions will be based on the ceramic "coin" type of capacitor using the attached schematic. I'm also assuming that a decoupling capacitor is the capacitor that connects the Vin to GND before the LM317; see C1 in schematic. Some post also mention a second decoupling capacitor connecting Vout to GND; see C2 in schematic, and that it is; under some circumstances, optional. The second capacitor should also be larger due to load variance on Vout.
The intent of decoupling capacitors is prevent oscillation. Oscillation from my comprehension is the fluctuation of Voltage and Current. So, the result in it's use with an LM317 is to aid in providing steady or "smooth" voltage and current. How it does this is analogous with an overflow gutter for a pool. When the circuit is powered the capacitors charge to it's rating. When voltage fluctuates up the capacitors discharge the "extra" voltage/energy to GND. When the voltage fluctuates down the capacitors discharge it's "stored" voltage/energy to the line it's adjacent/tapped into; i.e. Vin or Vout.
When soldering the capacitors for the through-hole type, it's best to have leads as long as possible. Something to do with the lead attributing to capacitance.
Also in the schematic 1N4007 is what they refer to as a "Protection Diode". And it's purpose is to prevent some type of current backflow from going into Vout which would damage the LM317.