# dc 5V to ac 5-10V

#### BC547

Joined May 22, 2018
40
Hello,

I need an AC source for my experiments but i have a 5V dc source. A dedicated AC controlled source is bulky and too much around the house. Therefore, I am looking out for a device, handy and that can do that. At the minimum I need 5V AC from a 5V DC supply. Second option i have is build my own, but since i am starting out it is a tough job.
Thanks,

#### KeithWalker

Joined Jul 10, 2017
1,393
What current, frequency and wave shape do you need? Do you need 5V rms, pk or pk-pk ?

#### BC547

Joined May 22, 2018
40
What current, frequency and wave shape do you need? Do you need 5V rms, pk or pk-pk ?
I need 5V peak to peak for breadboard stuff. The current is less than 10mA and frequency is moderate. Typically 1 kHz or less.

#### dl324

Joined Mar 30, 2015
12,224
I need an AC source for my experiments
This implies a sine wave.
I need 5V peak to peak for breadboard stuff
Do you really mean a clock source/oscillator?

#### BC547

Joined May 22, 2018
40
This implies a sine wave.

Do you really mean a clock source/oscillator?
Yes, a sinusoidal signal but not a clock source and that should be stable. I need to control its frequency regardless of its voltage. But for a start 5V peak to peak would be ok.

#### dl324

Joined Mar 30, 2015
12,224
Yes, a sinusoidal signal but not a clock source and that should be stable.
Unless you plan to work on analog circuits, you don't want a sine wave.

At any rate, here's an adjustable frequency circuit. You can integrate the triangle wave to get a sine wave (Nat Semi AN-31):

You can't get 5V peak to peak without using supply voltages higher than 5V. If you only plan to have a 5V supply, you can use a switching regulator to generate a higher voltage.

This circuit assumes dual supplies. For a single supply, you need to bias the grounded inputs to VCC/2.

#### dl324

Joined Mar 30, 2015
12,224
I bought a couple of these on Ali Express:

It doesn't list sine wave, but the board has a sine label and the description says it has sine wave output.

Prices have gone up since I bought mine. I paid less than \$8 for 2 with free shipping from this seller.

Doesn't satisfy your 5V p-p requirement, but you can add an amplifier.

#### bassbindevil

Joined Jan 23, 2014
147
See also the 8038 function generator kits. If you need more volts/amps, add an audio "chip amp" that's rated for a few watts; if you only have 5V power, add a DC-DC converter to get the voltage the amp needs.
Variable sine waves are useful for checking for mechanical resonances (rattles, buzzes, whines depending on frequency range) in speakers, headphones, and listening rooms (or cars).

#### rsjsouza

Joined Apr 21, 2014
266
I know you are just starting out but an oscillator at the frequency you are looking for is quite feasible with simple parts and a breadboard.

A reference that covers theory and I found very useful is the book Opamps for Everyone - chapter 15 talks about oscillators. This is a book sold at Amazon but there is an early revision in PDF that was published by TI many years ago and nowadays hosted in an education website.

Check this thread, which also contains other useful references:
https://www.eevblog.com/forum/beginners/opamps-for-everyone-pdf/

There is also a massive collection of projects from Colin Mitchell - look for 50 555 Projects (a PDF book) or simply search for the word "oscillator"