# Simple circuit Voltage regulator question?

I am trying to build a simple circuit that takes a 9v battery through a voltage regulator that outputs 1.5v across a load resistor . The load will be just a piece of metal that gets heated up.

My initial understanding of voltage regulators was wrong. I thought I wouldn't be wasting a lot of power using one, but from further reading I have discovered that they are just used for rectifying an ac source and when (vi-vout) is a large number a lot of power is dissipated/wasted as heat in the regulator. I want as much of the power from the battery as possible to be dissipated across the load resistor @ 1.5v.

So, my questions is how can I build this circuit with a 9v input and a 1.5v across load dissipated as heat with the smallest amount of wasted power through a regulator or other components?

• You need a switchmode converter. But how much heat are you expecting to get? 1 Watt would be a lot of power for a 9V battery. Mar 3, 2013 at 18:41
• Somewhere from 175 degrees C to 200 degrees C. I am going to use a load with a high resistance. So this switchmode converter won't dissipate a significant amount of power? I was hoping to make this as efficient as possible. Thanks.
– Sam
Mar 3, 2013 at 18:55
• I read up on switch mode converters and can see that they are significantly more efficient than using a voltage regulator. Thanks.
– Sam
Mar 3, 2013 at 19:11
• Do you think the LM25576 would be a good choice for my application? : ti.com/product/lm25576#buy Thanks.
– Sam
Mar 3, 2013 at 19:25
• I asked "how much heat", not "what temperature". What is it you're heating up, and how fast does it lose heat to the environment? Mar 3, 2013 at 20:30