Power Management in Noise-Sensitive Applications

Table 2 lists switching dc/dc step-down converters with desirable features for broadcasting applications.

Integration

If board space is at a premium, consider the modern power management solutions that integrate the switching DC/DC converter and post-regulation linear regulator into a single, small package. One such example is the TPS54120 from TI. Introduced only a little over a year ago in 2012, this device combines a high-efficiency switching DC/DC converter with a low-noise, high PSRR low-dropout linear regulator to support 1-A, noise-sensitive applications. The TPS54120 also includes switching frequency synchronization, soft-start, and power-good indication in a space-saving 3.5-mm x 5.5-mm thermally-enhanced QFN package.

Conclusion

In summary, power supply noise reduction is a complex subject. Part of a good power distribution system design is in choosing the right voltage regulators, the considerations of which have been mentioned. However, keep in mind that there are other important factors that are beyond the scope of this article, including proper bypassing, decoupling, damping, PCB layout, and much more. Thankfully, the internet is a great resource for additional information on these topics.

Landa writes from Dallas, TX. She holds a BSEE, and has 18 years experience in the electronics industry, from tech startups to Fortune 500 companies.