SLVAFV2 June 2024 LMR51610 , TPS629210
In battery power applications such as doorbells and E-locks, a buck converter is often required to obtain power rails with different voltage levels. To fully utilize the battery, the output voltage must be as close as possible to the input voltage in the dropout zone. This application note first introduces system power rails in battery power applications. We then discuss how to calculate, estimate and measure the voltage drop considering both the situation with or without temperature influence. The test data of TPS629210 and LMR51610 were used to verify the theory. A summary of this application note and how to choose a low voltage drop buck converter is proposed.