Tuesday, September 06, 2011

Analog Dialogue, Volume 45, Number 2

In this issue:
How to Apply DC-to-DC Step-Down (Buck) Regulators Successfully
AD7879 Controller Enables Gesture Recognition on Resistive Touch Screens
Low-Power, Unity-Gain Difference Amplifier Implements Low-Cost Current Source
Switch and Multiplexer Design Considerations for Hostile Environments (Ask the Apps Eng—40)
High-Resolution Temperature Measurement
Simple Op Amp Measurements

How to Apply DC-to-DC Step-Up (Boost) Regulators Successfully

Battery-powered systems often stack cells in series to achieve higher voltages, but this is not always possible due to a lack of space. Switching converters use an inductor’s magnetic field to alternately store energy and release it to the load at a different voltage. With low losses they are a good choice for high efficiency. Boost, or step-up converters—covered here—provide higher voltage.

Power Management Design for PLLs

Phase-locked loops are typically used to provide local oscillators in radio receivers and transmitters, for clock-signal distribution and noise reduction, and as the clock source for high-speed A/D and D/A converters. As PLL noise decreases, the impact of power supply noise increases, and can even limit noise performance in some cases. This article considers basic PLLs and the power-management requirements for each PLL building block.