Fundamentals of Choosing LDO and Switching Regulators
Although low-power DC/DC ICs often don’t get up-front attention and are viewed as commodities -- with selection often left to the last-minute -- the choice does affect performance, cost, efficiency, run time, PC board layout, and even overall product packaging.
Even for DC loads below 1A, developing the power-tree architecture and choosing the appropriate regulator ICs can be confusing. While a switching regulator seems like the obvious choice due to its inherent efficiency, the less-efficient low-dropout regulator (LDO) is still a good choice in many situations.
This course will explore issues including:
• supply-tree topology
• input and output voltage range
• thermal issues
• ease of use and additional components needed
• power distribution and physical board layout,
• application flexibility
• vendor sourcing and BOM issues
• design tools and techniques
As in most engineering situations, there is no single "right" answer, and the engineer must consider and balance the many tradeoffs involved in regulator selection and design-in.