I am designing a security camera that needs battery back-up. It will have a 12v power supply to power it most of the time, but if that power supply fails, then it will need to switch to its internal battery back-up.
I am looking for an IC which always maintains the 5v SYS voltage. If the 12v is connected and working, then it uses that source to supply the 5v SYS voltage, and maintain the 3.7v battery. If the 12v power fails, then it boosts the 3.7v battery to keep supplying the 5v SYS voltage.
I.e. the chip needs to be able to charge the battery and maintain the 5v SYS voltage at the same time.
An I2C interface to monitor the battery would also be useful.
Thanks for reaching out on the MPS Forum. I can recommend the MP2720 | 2.5A, Single-Cell NVDC Buck Charger | MPS. This part has capabilities to use the battery and input voltage to maintain a 5V system voltage. Other parts with a hgiher charge current can be the MP2722.
For other products with capabilities you are looking for, you can use the filter on this page using “Narrow Voltage Power Path Management” Chargers - Battery Management - Products
Thank you for the suggestion. I may be misunderstanding the datasheet, but it looks to me like this part can supply 5v to the IN (input voltage) pin for USB-OTG, not the SYS (output voltage) pin, which powers my application.
Do you have a part which can guarantee that the SYS voltage is always 5v, no matter if the input power supply is connected or not?