Hello,
For my project i nead 5v from a 12v battery. So i try to use this.
The consomption of my device nead to be the most low possible.
I check the amper of the dc dc converter without connecting someting and surprise the comsomption is 25mA. How it is possible. I nead a DC DC converter with no comsomption or in uA. Is that possible ?
Thank you for your help
The MP1584EN chip can perform much better than this, perhaps its a poor circuit or a counterfeit?
You can never get zero power consumption from a DC-DC converter unless it is disconnected.
Some are optimized to give very low consumption at zero load. It should be possible to find ones in the uA range. The specification you are looking for is "quiescent current".
Here is one example from Pololu That web page claims 100uA quiescent current and there's a few options for reducing that even further with that device.
The MP1584EN chip does have 100uA quiescent current, that module is clearly not reflecting that, I strongly suspect its counterfeit / substitute chip.
The MP1584EN chip does have 100uA quiescent current, that module is clearly not reflecting that, I strongly suspect its counterfeit / substitute chip.
That could be, but the chip specs are just the chip specs. There are other components on the board and there may be legitimate design considerations for an overall design with higher quiescent current. Or maybe is just a poor/cheap circuit design... In general, you can't just solder a chip on the board and get optimum or "advertised" performance.
I'd assume the quiescent current is for the whole conversion circuit, these chips are single-purpose.
Look at the Polou module documentation. There is a pullup resistor that increases the power consumption.
The datasheet for the chip can't include that. And even if it could, the marketing department won't allow it. The datasheet will usually give you the most favorable number possible without actually lying.
A pullup resistors not going to account for 25mA of extra current!!
Datasheet says the quiescent current is 125uA.
Thank you for your help. I will look for a DC DC converter with better quiescent current.