Wednesday, 17 June 2015

voltage - Using pot as variable resistor: should wiper be connected to spare end terminal?


I've heard somewhere that a rheostat uses two pins while a potentiometer uses three. But still, the thing i would like to know is if there's anything different with the adjustment if I wire the pots like this:


enter image description here


Or will it not matter how I wire it? Thanks!



Answer



Electrically, these 2 circuits are equivalent. However, the advantage of the circuit on the right is that if the internal moving tap loses contact with the resistive element, the circuit still appears as a resistance rather than an open circuit. The latter can cause problems with some applications (for example, causing a voltage regulator to lose regulation or generate a large voltage). That is why most designers use the circuit on the right.


No comments:

Post a Comment

arduino - Can I use TI's cc2541 BLE as micro controller to perform operations/ processing instead of ATmega328P AU to save cost?

I am using arduino pro mini (which contains Atmega328p AU ) along with cc2541(HM-10) to process and transfer data over BLE to smartphone. I...