Portable DVD needs 9.5v DC input - is 9.0 or 12.0 v better?

MichaelD

Lifer
Jan 16, 2001
31,528
3
76
I have a portable DVD player. It has an external DC input rated at 9.5v DC. I have a DC adapter which can be switched b/t 9.0v and 12.0v DC. I'm thinking undervolting by .5v is the better idea....but I'm not an electrical engineer/math type guy. Which voltage is better? Thanks.

ps
Waiting for the "Nuke it from an orbiting space station...that's the only way to be sure" reply.

pps
There. I said it. Now please give me a real reply. :p
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
Would a dvd player have a voltage regulator to knock the voltage down to 9 volts?
 

Jeff7

Lifer
Jan 4, 2001
41,596
19
81
A 9.0V adapter will probably put out a bit more than 9V anyway, though that will fall with increasing load.

And of course, make sure that the input supply's rated amperage output is more than the device's rated current draw.

 

mrSHEiK124

Lifer
Mar 6, 2004
11,488
2
0
Another vote for 9V; for the same reason most CE can handle the 1.2-1.3V of NiMH AAs when they're expecting 1.5V. As long as you've got extra current from the adapter you'll be fine.
 

Sasiki

Senior member
Oct 18, 2004
589
0
0
9v, but make sure that the power supply outputs more amps than the device draws. The power supply will say the output amps and the DVD player will say on it somewhere what the input amperage is. As long as the power supply outputs more than the DVD player inputs, you'll be fine.
 

BoomerD

No Lifer
Feb 26, 2006
65,271
13,538
146
Dood...go with the 12 volts...You'll get a cleaner picture and more volume! :roll:
OR, you COULD get the proper power supply for the unit...
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
9.0V.

Don't use 12V on it, you'll fry it.

9.0V should work OK though.
 

MichaelD

Lifer
Jan 16, 2001
31,528
3
76
Thanks very much, everyone! 9.0 volts it is. I will be sure to check the amp draw...but I'm sure I'll be fine with 9.0v. I'll be using the DVD player only as a monitor, displaying an external source...the DVD drive won't be spinning a disc...lot less juice needed.

Thanks again. :thumbsup::)
 

bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
Definitely don't do 12V.

Don't use 12V on it, you'll fry it.

^^^ Possibly wrong, possibly right. If you took it apart and discovered a regulator circuit 12V would be just fine. You won't fry it. However if not there is a very good possibility that the magic smoke will come out.

What is the amperage rating on the 9V vs the 12V adaptor? If the 9V is 100ma, and the 12V is 1200ma, and the device needs 800ma to work - well the 9V will not cut it and would likely either completely die or get incredibly hot and possibly catch fire.

More important - which one actually fits?

I'm willing to bet - but not with any real money or anything - that the 12V adaptor will work just fine, as will the 9V adaptor. In this case - monitor the device and use the one that generates the least heat for both devices.
 

PottedMeat

Lifer
Apr 17, 2002
12,363
475
126
^yeah if you open it up and look at the circuitry just after the power jack and look up the IC - if it's a switching regulator it may be perfectly fine with 12V (whatever it's input range is ). If its a linear regulator it may be fine too, but generate lots of heat.