DESIGN VIEW is the summary of the complete DESIGN SOLUTION contributed article, which begins on Page 2.
The frenetic pace of advances made in semiconductor process technologies inevitably increases the speed and density of IC devices. Many of these devices, such as DSP-based communication and digital TV ICs, are being designed into systems that traditionally employed lower-performance, dedicated peripheral devices. Designers, however, need to treat the power requirements of these high-performance devices with care.
Because power circuits can be challenging and time-consuming to design, many engineers opt for off-the-shelf dc-dc converter modules. This choice reduces risk and effort, but it may cost more and come up short on performance. For this reason, an in-depth cost/benefit analysis often highlights the advantages of a discrete converter design based on a commercially available step-down (buck) converter IC.
The load response, frequency, power capability, and other specifications of these discrete designs can be more finely controlled to meet critical design criteria. By following 10 key design tips, designers can achieve excellent results in dc-dc power-converter designs for high-performance CMOS ICs. The 10 tips, discussed in detail, are:
- Plan your power section first.
- Give each high-power device its own converter.
- Isolate power and ground sections.
- Don't overestimate the regulator's load response capabilities.
- Provide proper bypass capacitors, large and small.
- Give careful thought to capacitance values and ESR.
- Don't forget the input.
- Remember Ohm's Law.
- Understand that capacitors differ.
- Measure the noise.
Full article begins on Page 2