Can one power a monitor that uses a 19V power adapter using 12V adapter ?

SPK123

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Mar 7, 2017
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Can one power an LED monitor that uses a 19V power adapter, with a 12V power adapter ?

Wouldn't the 19V DC power be stepped down to 12V power before being used by the monitor ?

So, can one rather use a good quality 12V power adapter to provide DC power ?
 
Solution
You are making assumptions about how the monitor power supply works without any basis for them. A 12V adapter is unlikely to damage the components, but it is possible depending on the design and that's why I mentioned it. The likelihood is probably vey tiny though so you can probably ignore that bit. The rise in current you mention would happen on the input to the monitor and therefore it would have to be able to handle it.

The simplest answer if you have one is plug it in and see, I just can't 100% guarantee it's safe to do so (probably is)

Why would you assume the monitor uses 12V internally, and that it steps it down efficiently. Most logic circuits are less than 5V. Most likely the 19V input is converted to several different...

Dugimodo

Distinguished
You'd have to ask the manufacturer, there's no blanket answer. Some monitors would likely work and others wouldn't, reducing the voltage may draw excess current and damage components in extreme cases or more likely simply not work. It all depends what kind of power supply circuitry they have used, there does tend to be a tolerance and a range of input voltages that will work, but nobody but the manufacturer will know what that is. I'd stick with the proper supply or a compatible replacement personally.
 

SPK123

Prominent
Mar 7, 2017
24
0
510


Thank you for the response

Why would a 12V adapter damage the components, if the 19V DC x 4A for 76W input is going to stepped down by the monitor to 12V 6.33A for 76W ?

Wouldn't the monitor itself ultimately increase the amperage to to 6.33A if 19V 76W is stepped down to 12V 76W by the monitor itself ?

So, can one rather use 12V 8A 96W adapter to power the monitor ?

76W is maximum power consumption of the monitor.
 

Dugimodo

Distinguished
You are making assumptions about how the monitor power supply works without any basis for them. A 12V adapter is unlikely to damage the components, but it is possible depending on the design and that's why I mentioned it. The likelihood is probably vey tiny though so you can probably ignore that bit. The rise in current you mention would happen on the input to the monitor and therefore it would have to be able to handle it.

The simplest answer if you have one is plug it in and see, I just can't 100% guarantee it's safe to do so (probably is)

Why would you assume the monitor uses 12V internally, and that it steps it down efficiently. Most logic circuits are less than 5V. Most likely the 19V input is converted to several different voltages for various circuits within the screen maybe with DC-DC circuitry but possibly just using simple regulators for some of it (which just waste the excess voltage).

With a regulator providing your input voltage is high enough to provide the output voltage it will work just fine, with a DC-DC converter if the input voltage lowers the current will have to rise to compensate. Either will work over a range of voltages but you can't just assume 12V is enough, if it was why wouldn't they supply a 12V supply to begin with.
 
Solution