AJBotha
Newbie level 6
Hi Guys
I am working on a project that is in essence a "smartish" power supply bus. The AC/DC is managed by an off the shelf PSU, so no real work there.
A microcontoller controls power to 4 sets of downlinks, controlled by FETs. If something goes faulty down the line I can switch off the supply to that bus and notify the system admins.
The supply voltage (read: bus output) should be between 48V and 55V. 48V seems cheaper at this stage and I suspect I will go for a 48V bus (DC).
The power supply has back-up lead-acid batteries, they need to be charged. If I went with the 55V bus I could series 4x 12V (48V battery backup) batteries and still have enough left (from AC/DC supply) to charge them with.
If I go for the 48V bus, I wont have enough voltage to charge the array effectively. The I will look at 24V battery backup, which is also acceptable for the output bus, even though less efficient.
My actual question is how do I charge the backup batteries - options seem either very inefficient or horribly complicated! I think a switching battery charger IC is the way that I would like to go.
My requirements would be mostly maintenance charging (float charging) and if the batteries go below Vmin to charge them at 1A or whatever. I am more interested in a smart/efficient maintenance charger than a 5 minute 50Amp charger! Do you have any leads that I can investigate?
The Texas Instruments BQ2031 seems easy enough to use, but it can only work from 5V, a voltage I don't have available and don't necessarily want to introduce for a single IC.
The Linear Technology options seem pretty complicated and probably expensive, and also seem to require more external parts. But it can operate from supply voltage up to 55V.
If you can maybe help, please do. I am inexperienced but eager to learn!opcorn:
I am working on a project that is in essence a "smartish" power supply bus. The AC/DC is managed by an off the shelf PSU, so no real work there.
A microcontoller controls power to 4 sets of downlinks, controlled by FETs. If something goes faulty down the line I can switch off the supply to that bus and notify the system admins.
The supply voltage (read: bus output) should be between 48V and 55V. 48V seems cheaper at this stage and I suspect I will go for a 48V bus (DC).
The power supply has back-up lead-acid batteries, they need to be charged. If I went with the 55V bus I could series 4x 12V (48V battery backup) batteries and still have enough left (from AC/DC supply) to charge them with.
If I go for the 48V bus, I wont have enough voltage to charge the array effectively. The I will look at 24V battery backup, which is also acceptable for the output bus, even though less efficient.
My actual question is how do I charge the backup batteries - options seem either very inefficient or horribly complicated! I think a switching battery charger IC is the way that I would like to go.
My requirements would be mostly maintenance charging (float charging) and if the batteries go below Vmin to charge them at 1A or whatever. I am more interested in a smart/efficient maintenance charger than a 5 minute 50Amp charger! Do you have any leads that I can investigate?
The Texas Instruments BQ2031 seems easy enough to use, but it can only work from 5V, a voltage I don't have available and don't necessarily want to introduce for a single IC.
The Linear Technology options seem pretty complicated and probably expensive, and also seem to require more external parts. But it can operate from supply voltage up to 55V.
If you can maybe help, please do. I am inexperienced but eager to learn!opcorn: