I recently purchased a sine wave generator circuit from China for a project. Of course, being from China, it was inexpensive, but came with no directions or support. I need to hook up power and the only thing it says is:
Over 3W dual 10-16V AC transformer or dual 15-22v DC power supply can work.
There are three connection points for power, with the middle one marked "ground". Can anyone help a novice tinkerer like me out by telling me what I can hook up to this to power it and how?
Thanks and God bless
Over 3W dual 10-16V AC transformer or dual 15-22v DC power supply can work.
There are three connection points for power, with the middle one marked "ground". Can anyone help a novice tinkerer like me out by telling me what I can hook up to this to power it and how?
Thanks and God bless
It sounds like the power input requires a pair of transformer secondary windings, connected in series with the right polarity (dot-to-no-dot),
and with the center tap connected to the middle ground terminal. The needed rectifier diodes are already built in to the board.
The transformer secondaries should be rated between 2 x 10VAC and 2 x 16VAC.
The current rating should be at least 150mA AC for each of the two windings.
A shot of the board, especially focusing on the power supply input would help. Most likely you can use two of your laptop power supplies in series, so you end up with something like -19.5V, 0V and +19.5V. However, since the power requirement is low (only 3W), using your laptop PSU is overkill (they can supply at least 60-100W). The transformer is cheap, i suggest you get it instead and save your laptop PSU for something else needing much higher power.
http://www.radioshack.com/radioshac...t-xformer-w-leads/2731365.html#start=13&sz=12 This will work for this purpose.
Here is a link to the item on Ebay. You can't see it in the photos, but all 3 power terminals connect to the adjacent IC.
New DDS Function Signal Generator Module Sine Square Triangle Wave | eBay
I will pick one of these up, but please check back on this thread as I will probably want to ask if I have everything hooked up correctly before plugging it into the wall.
Thanks.
There is a bridge rectifier and a pair of electrolytic capacitors on the back.
That indicates that a 3lead AC supply from a Centre Tapped transformer is required.
I can't read the voltage rating of the caps. This determines the absolute maximum voltage you can input to the rectifier.
A 16+16Vac transformer of 3VA size could output {16+16}* mains overvoltage * transformer regulation = ~ 46Vac
Convert to peak for the rectified voltage and you get a bit less than 64Vdc split between the two caps. i.e. 16Vac could give a worst case 32Vdc on each capacitor.
To send out a part complete "kit" without instructions is typical of the poor customer service we get from these "fly by night" retailers.
A negative feedback, warning other customers of the situation is deserved.
That indicates that a 3lead AC supply from a Centre Tapped transformer is required.
I can't read the voltage rating of the caps. This determines the absolute maximum voltage you can input to the rectifier.
A 16+16Vac transformer of 3VA size could output {16+16}* mains overvoltage * transformer regulation = ~ 46Vac
Convert to peak for the rectified voltage and you get a bit less than 64Vdc split between the two caps. i.e. 16Vac could give a worst case 32Vdc on each capacitor.
To send out a part complete "kit" without instructions is typical of the poor customer service we get from these "fly by night" retailers.
A negative feedback, warning other customers of the situation is deserved.
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