Boost converter

[Ronnie Ssejjuko]

hello everyone, I am trying to design a boost dc-dc converter to step up my 1.5V voltage from a thermoelectric generator to 12V. I have tried to look at several circuit designs such as using a mosfet with an inductor or using a BJT with an inductor, but I am worried that I am not getting results. please help on how I can best do this. Thanks

 

[AnalogKid]

Post the designs you are considering and we can discuss them.

ak

 

[dr pepper]

If you google 'joule thief' you'll find lots of answers, such a circuit is easy to build, though 12v may not be that common, most seem to be used for lighting leds, from 0.6v upwards.

 

[ronsimpson]

You understand that while the voltage goes from 1.5 to 12 the current will go from 10 to 1.

 

[large_ghostman]

Linear technology make boost converters especially for them

 

[Nursyukriah Idris]

Hi.. can anyone help me to design a boost converter with low power application. The input voltage is too small which is 0.15 V. I want to use boost converter to step up that voltage to be 1.5 V. It is suitable to use boost converter to boost up that smallest input voltage?

 

[spec]

Hi.. can anyone help me to design a boost converter with low power application. The input voltage is too small which is 0.15 V. I want to use boost converter to step up that voltage to be 1.5 V. It is suitable to use boost converter to boost up that smallest input voltage?

Hi Nursyukriah, welome to ETO.
I am afraid you are not allowed to hijack another persons question with your own question on a new topic. It is against ETO rules.

If you open a new thread of your own you are bound to get plenty of help from ETO members. A good title for your new thread would be 'Boost 150mV to 1.5V?'
spec

 

[bountyhunter]

hello everyone, I am trying to design a boost dc-dc converter to step up my 1.5V voltage from a thermoelectric generator to 12V. I have tried to look at several circuit designs such as using a mosfet with an inductor or using a BJT with an inductor, but I am worried that I am not getting results. please help on how I can best do this. Thanks

Most important spec you forgot to state is how much load current it must supply. But to answer your question: it is very easy to boost 1.5V to 12V, I have published app circuits for it. The easiest way is to use a free running 555C and coil with a 12V zener diode.

 

[ronsimpson]

The easiest way is to use a free running 555C

Will the 555C run at 1.5 volts supply?

 

[bountyhunter]

Will the 555C run at 1.5 volts supply?

Sorry, I meant to write LMC555. I am a little dyslexic. The CMOS version does run down to 1.5V.

https://www.ti.com/lit/ds/symlink/lmc555.pdf

 

[MrAl]

Hello,

Didnt the OP say they wanted to step up 0.15v to 1.5v ?
That's much lower than usual and would require special design considerations.

 

[ronsimpson]

Look at the AP3015A. In the data sheet they show two examples. 1.2V to 2.5V in 3.3V out and another circuit with 20V out. The current is low.

 

[ronsimpson]

Sorry, I meant to write LMC555. I am a little dyslexic. The CMOS version does run down to 1.5V.

LMC555
At 12V supply the "high level current" is 10mA
At 6V..............4.7mA
At 1.5V........0.26mA
While a real boost PWM has a 300mA switch at 1.2V.

 

[ronv]

 

[ronsimpson]

Hay! You can't use my picture with out copy right permission!

 

[dr pepper]

Thats me when the tax bill comes.

 

[bountyhunter]

LMC555
At 12V supply the "high level current" is 10mA
At 6V..............4.7mA
At 1.5V........0.26mA
While a real boost PWM has a 300mA switch at 1.2V.

???? I never said it was a single part solution. You use a three cent external transistor (2N3904) as the coil's switch device driven by the output of the C555.

Like I said: if the user would post the load current the 12V line has to supply, I could say whether this solution is feasible. It is a working circuit (published) for relatively low power applications. With 1.5 VIN, it can put out 12V at a couple of milli amps.

 

[spec]

I was reading about this TI PSU chip for a similar application. Any interest: https://www.ti.com/lit/ds/symlink/tps61020.pdf

spec

 

[kubeek]

Guys, 1.5V from the original original poster does not equal the the 0.15V the new OP is asking about.
Ya(almost)´all should know better and read the whole thread and check the dates beforehand
Edit: Hats off to Ronv, partial hats off to spec who noticed first, but on the other hand then forgot all about it and found a chip that runs from 0.9V

 

[spec]

Hello,

Didnt the OP say they wanted to step up 0.15v to 1.5v ?
That's much lower than usual and would require special design considerations.

Guys, 1.5V from the original original poster does not equal the the 0.15V the new OP is asking about.
Ya(almost)´all should know better and read the whole thread and check the dates beforehand
Edit: Hats off to Ronv, partial hats off to spec who noticed first, but on the other hand then forgot all about it and found a chip that runs from 0.9V

Hello somebody is not following all the posts in this thread.

I mentioned in post #7 to the second poster, Nursyukriah Idris, that her post #6 was a highjack. Since then she has opened a new thread asking about her project (150mV): https://www.electro-tech-online.com/threads/boost-150mv-to-1-5v.147660/
spec