I’m building a device about the size of a piece of furniture that has a 24v line for stepper motors (it could be 20 or 30… but run much better than with 12v), then a number of cards running at 5v for NFC, wifi, TFT display and various sensors.
The whole thing is supposed to be “low voltage” from a safety perspective and was thinking of using a laptop charger (from a known brand) as the power source (these seem to be good value compared to power supplies sold specifically for electronic devices). Then, since the device should be able to work for short periods in case of power disruption, including a sealed lead acid battery in the power chain.
I’m not experienced in these matters, any comments on the following (schematic attached) much appreciated:
Laptop charger provides 19.5v and runs to BQ25703A (buck/boost) battery manager which generates the approximately 14v necessary to charge a 12v SLA battery.
The battery is then connected through a LM5050-1 OR to a LM5121 boost convertor to raise the voltage to the required 24v.
The 19.5v line in also passes directly through a LM5050-1 OR to the same boost convertor to attain 24v.
(Wherever 5v is required in the circuit there will be a small buck, TPS62175.)