I am designing a 3V battery-powered simple micro-controller to collect sensor data in RAM. How can I avoid a conflict with the 5V of a USB when it comes time to upload the data? Disconnecting the battery would lose the RAM. The solution needs to be very simple as the PCB is very small.
There are two possible options based on the limited infomation you have provided
- Consider storing data in Non-Volatile Memory.
- Use a LDO such as TPS73633 that can support wide input voltage range TPS73633 support a range of 3.5V and 5.5V. The output is 3.3V. An provide both the supply voltage options.