Voltage Input-to-Output Control for Linear Regulators : Quick Start and Benefits

Part 1 of this two-part series introduces voltage input-to-output control (VIOC) systems that are commonly configured as a combination of low dropout (LDO) regulators with the VIOC feature and buck-topology switching regulators.

- By: Andrew Radosevich

The article then gives guidance for VIOC system design, including a list of suggested pairs of LDOs and switching regulators and the reasons for the pairing. Lastly, it shows how use of the LDO’s VIOC feature can reduce noise at the LDO output, optimize power dissipation, protect the system during faults, and ensure proper operation during dynamic conditions like startup and overload. Part 2 expands on the guidance for VIOC system design from Part 1 and also discusses VIOC theory of operation and background.

In the realm of power management, low dropout (LDO) regulators play a crucial role in ensuring high performance power delivery to electronic components. Low noise performance in LDOs is vital, especially in noise-sensitive applications like precision analog circuits, RF systems, and medical devices, where LDOs ensure clean power delivery, minimizing interference and enhancing signal integrity. When combined with voltage input-to-output control (VIOC) functionality and a compatible switching regulator to provide the LDO with power, LDOs can further enhance their performance by creating a system that consistently maintains an optimal input-to-output voltage for noise-minimizing, high power supply rejection ratio (PSRR), in addition to operation that is efficient, protected, and highly capable.

This article delves into the intricacies of implementing VIOC, exploring its advantages and practical applications. By understanding the synergy of VIOC, engineers can optimize power management solutions for a wide range of electronic devices.