Minimizing Switching Regulator Residue in Linear Regulator Outputs

Focus:

When linear regulators are used to post regulate the outputs of switching regulators, they have difficulty suppressing the ripple and spikes produced by the switchers. This problem gets worse as the voltage across the linear regulators (VIN-VOUT) is reduced. The causes of the linear regulator's poor rejection of ripple and spikes are discussed. A hardware simulator is described that generates ripple and spikes, enabling designers to evaluate and optimize linear regulator performance for ripple and spike rejection. The simulator is used to demonstrate the effects of changing output capacitance or adding ferrite beads on ripple and spikes.

What you’ll learn:

• How to minimize switcher-generator ripple and spikes on the output of a linear post regulator

Notes:

Linear Technology Application Note 101

View the Source

Author & Publication:

Jim Williams, Linear Technology, Vendor website, Jul 01 2005

This article summary appears
in the HOW2POWER Design Guide.

The Design Guide offers
organized access to
hundreds of articles
on dozens of power conversion
and power management topics.

The Design Guide search results
include exclusive summaries
and accurate "how to" analysis
to help you make faster,
more informed decisions.

Search
for more articles