Powering Lilliput from AC source

**hevnsnt** · 04-25-2004, 04:03 PM

I bought my Lilliput from a group buy, and it came with a foreign ac/dc converter. So I went to Radio Shack and bought this one but before I plugged my lilliput into it I checked it with my multimeter.

It is pushing 14.86 volts. Is this going to fry my Lilliput?

**jusatry** · 04-25-2004, 04:35 PM

i have that same 12 V adaptor, and it puts out 14.xx volts for me too....i dunno about the lilli though.....hrmmmm

**hevnsnt** · 04-25-2004, 04:39 PM

do you use it for your lilli?

**gork** · 04-25-2004, 05:05 PM

Measuring the output of most DC "wall wart" style power supplies won't give you the true voltage. A 12V adaptor could easily measure 14-20V with no current load. If you pull 1.5A through it (its rated load) it would measure 12V. If you have some calibrated load resistors, you can make a proper measurement, but if not, just trust the labelling on the power adaptor. Some adaptors will have built-in voltage regulators that keep a constant voltage up to the rated current. These will normally measure closer to what they say, although if you have a device like the lilliput that will pull a pretty constant load, it's not a very necessary part of the PSU design.

Check to make sure that you have the right end set up for center (tip) positive, and that adaptor will work fine for your lilliput. Incedentally, the wall wart that the lilliput ships with is a non-regulated design (like your radio shack adaptor) and the car power adaptor has a regulator in it.

**hevnsnt** · 04-25-2004, 05:51 PM

Originally Posted by gork

Measuring the output of most DC "wall wart" style power supplies won't give you the true voltage. A 12V adaptor could easily measure 14-20V with no current load. If you pull 1.5A through it (its rated load) it would measure 12V. If you have some calibrated load resistors, you can make a proper measurement, but if not, just trust the labelling on the power adaptor. Some adaptors will have built-in voltage regulators that keep a constant voltage up to the rated current. These will normally measure closer to what they say, although if you have a device like the lilliput that will pull a pretty constant load, it's not a very necessary part of the PSU design.

Check to make sure that you have the right end set up for center (tip) positive, and that adaptor will work fine for your lilliput. Incedentally, the wall wart that the lilliput ships with is a non-regulated design (like your radio shack adaptor) and the car power adaptor has a regulator in it.

Excellent info.. THANK YOU VERY MUCH.

I just didn't want to fry my lilli 30 secs after I took it out of its box.

**MatrixPC** · 04-25-2004, 06:03 PM

The output from the Lilliput AC plug is 12.50V with 5% tollerance (base on my multimeter spec)
Your best bet is buy one of those 2-3 prong converter and drill the other end to accept "circle" instead of flat.