capacitor use problems

[Nipuna56]

why capacitors use in voltage regulator circuit what is the use of it

 

[jeffrey samuel]

They filter the op from the regulator ckts

 

[internetuser2k12]

why capacitors use in voltage regulator circuit what is the use of it

To remove the ripples from the rectified and regulated DC output

Check this link. http://www.electronics-tutorials.ws/diode/diode_6.html

 

[jeffrey samuel]

They are also used along with Zener diodes for more rectification of AC signal

- - - Updated - - -

They are also used along with Zener diodes for more rectification of AC signal

 

[Nipuna56]

if we use DC power supply for our project still need that cap?

- - - Updated - - -

if we use DC power supply for our project still need that cap?

 

[jeffrey samuel]

No In DC supply the cap is open circuited so here they are used to generate OPEN CKTS that let current to flow through the parallel path without any loss

 

[internetuser2k12]

Yes if there is no capacitor in the power supply.

 

[jeffrey samuel]

Yes if there is no capacitor in the power supply.

Where my pal Be more specific in it

 

[Nipuna56]

if i don't use caps what can be seen
or what wrongs that can appears

 

[jeffrey samuel]

In the case of DC supplies consider this if the supply is distributed parallelly and if you don't want current to flow through one path then we use a capacitor as the reactance of the cap is almost infinity in case of DC supplies so we go for it



In AC ckts they have many purposes the Filter the ripples by consequetive charging and discharging
in resonant ckts they are used to tune the frequency and many more

 

[Nipuna56]

if i don't use caps some times voltage can varying?

 

[jeffrey samuel]

In a rectifier circuit if you don't use a Capacitor you will get pulsating DC cycles and so the op voltage will vary

 

[Nipuna56]

tanx friend another one
how zener diodes work and i so some regulated circuit use these diodes what are the use of it

 

[jeffrey samuel]

capacitor is a filter and even after filtering there is a small amount of ripple in the op this is removed by the ZENER diode it almost completely removes the AC component from the signal

 

[Nipuna56]

how zener works?

 

[jeffrey samuel]

Zener in the reverse Bias acts as an voltage regulator right based on that it works

try to see https://en.wikipedia.org/wiki/Zener_diode#Uses

 

[Nipuna56]

we can get good regulated output using higher value capasitor

(if we use 100uf we can get better out put )

is that correct?

 

[jeffrey samuel]

that depends not only on the capacitor but also the time constant of the capacitor in use that means the resistance and the capacitance needs to be high

higher the capacitance more time takes for the cap to completely discharge there by the rectification is more in the case of higher order caps

 

[Nipuna56]

i have seen in some regulated circuit two 100uf and two 0.1uf using near 78xx regulator please explain this

 

[jeffrey samuel]

post the schematic for us to explain it more precisely