Is this possible (DC to DC step up)

[joecool85]

I want to get +/-24 volts out of my car's 12v system. Is that possible?

 

[Nigel Goodwin]

I want to get +/-24 volts out of my car's 12v system. Is that possible?

Yes, it's what's used in 'high power' car amps. It's called an inverter, it's a SMPS that basically converts the DC to AC, feeds it through a transformer, and then converts it back to DC again. They generally have feedback from the secondary, to regulate the output voltage.

A LOT though depends on exactly what you are wanting to do, and how much power you need!.

 

[joecool85]

I want it to run a couple lm1875s. They make 20wRMS or so.

 

[Nigel Goodwin]

I want it to run a couple lm1875s. They make 20wRMS or so.

How about using a couple of TDA1562Q instead?. They provide 30W RMS from a 12V supply!.

 

[joecool85]

Wow, I didn't know about those ones.

**edit**
Where can I find these chips?

 

[Nigel Goodwin]

Wow, I didn't know about those ones.

**edit**
Where can I find these chips?

How about trying google?.

I did, and found this amongst many!.

 

[joecool85]

I checked jameco and partsexpress and stopped there lol. Thanks for the link. I don't think I'll use them though, looks a shade complicated.

How hard would it be to get +/-15 out of an automotive system? Or even +/-12? I'm thinking of using a TDA2030 for another automotive project.

 

[audioguru]

How about using a couple of TDA1562Q instead?. They provide 30W RMS from a 12V supply!.

If your car battery is being charged at 14.4V, the TDA1562Q provides 55W at low distortion to a 4 ohm speaker.

I wonder if you can hear it switch its supply voltage?

 

[Nigel Goodwin]

I checked jameco and partsexpress and stopped there lol. Thanks for the link. I don't think I'll use them though, looks a shade complicated.

How hard would it be to get +/-15 out of an automotive system? Or even +/-12? I'm thinking of using a TDA2030 for another automotive project.

It's a LOT more complicated building a DC/DC converter than using the IC I suggested above!.

 

[audioguru]

Use a simple bridged amp for car radios. They give about 14W into a 4 ohm speaker with low distortion at clipping. About the same amount of power as an LM1875 or TDA2030 that uses a voltage doubler circuit.

 

[joecool85]

Do you have an example of such a circuit?

 

[audioguru]

Do you have an example of such a circuit?

Philips makes more than 76 amp ICs and ST Micro make at least 40. Here is a simple stereo amp from Philips. The datasheets usually have a pcb layout for the circuit.