How to use Zener diode as a regulator??

[gameelgamal]

how to use zener diode

Hi
I have 12 V battery
and I want to use it to drive 6V 3A DC motor

First, I choosed 7805 regulator, But it got too hot
So I want to design a regulator circuit using Zener diode
But I dont have any experience in this field..

Any help...

 

[srhoar]

how to use zener diodes

A 7805 only sources 1A. That is why it got hot.

Red

 

[barrybear]

zener diode shunt motor regulator

I would not use the dc regulator that you have chosen to provide that sort of current .
You realy need to use a pulse of current with the duration of the pulse verying that way you will get the best control with little heat generated in your control circuit.
The same method i described is used in hand held electric drills . You can hear the inverter working as you pule the triger for more power

 

[Kral]

how to use diode

gameelgamal,
Barrybear is correct. to use a Zener diode in a simple shunt regulator configuration, the series resistor would have to dissipate (12-6)*3 = 18 Watts. Furthermore, if you remove the 3A motor load, the Zener would have to also have to dissipate 18 Watts. This simplified analysis assumes that the Zener current under the 3 A motor load is negligible. The only practical way to provide the regtulation is to use a switching buck regulator. It would waste very little power and greatly extend the battery life.
Regards,
Kral