# DC current amplification without changing the voltage.

#### Swapnil Wankhede

Joined Jan 10, 2017
1
Hey Guys,
I am designing an electronic circuit for theater lighting. I am using (12v/ 35watt / 0.15 amp) DC bulbs. The input is 230v AC supply and I have connected a step down transformer, a rectifier and a zeiner diode (for constant voltage). I need the output to be 12v and 2.1 ampere. can someone help me amplify the output current from >1 ampere to 2.1 ampere dc. Is it possible to do so with a Bipolar Junction Transistor ?

#### crutschow

Joined Mar 14, 2008
27,718
What is limiting the current to >1 ampere?
A transistor cannot amplify current that isn't already available.

#### WBahn

Joined Mar 31, 2012
26,398
Furthermore, this doesn't sound like a reasonable application for a zener diode. Could we see your proposed circuit?

#### AlbertHall

Joined Jun 4, 2014
11,500
(12v/ 35watt / 0.15 amp) DC bulbs
12V and 35W implies that the current is 3A, whereas 12V and 0.15A implies a wattage of 1.8W?

#12

#### #12

Joined Nov 30, 2010
18,223
This is one way to use a relay to amplify 12 VAC into 12VDC at 2.1 amps.
If you used 4 diodes you could make the transformer and the capacitor smaller.

#### AnalogKid

Joined Aug 1, 2013
9,353
1. 35 W at 12 V is 2.92 A, not 0.15 A, and error of 1945%. Please repost with correct numbers.

2. To regulate a power source at that power level can be done with a zener diode, but the result will be extremely inefficient and relatively expensive. Without getting into regulator circuits using ICs, there are simple regulator circuits that will perform adequately for your application. Do you have access to power transistors like a 2N3055 or TIP41?

What are the max and min output currents the supply will have to deliver?

ak