A simple route to dc power-rail loads News & Analysis 4/27/1999 Post a comment A hot-swap power manager (HSPM) can be used to design a simple, programmable, constant-current electronic load for 3-V to 5-Vdc power rails. Ordinarily, maximum current capability is limited to 2.7 A for this part type, but higher currents can be obtained using external n-channel MOSFETs. The current would then be limited only by the safe operating area of the FET. An undervoltage lock-out trigger on the Unitrode UCC3919 prevents operation when the input power rail is below 2.75 V.
DSP frameworks send voice over IP News & Analysis 4/27/1999 Post a comment Voice-over-Internet-Protocol (VoIP) is the recognized industry term to categorize the array of telecommunications equipment and services that are stimulating the transition from traditional circuit-switched to packet-data-based equipment networks. The technology changes required with the shift from the transport of packet data over voice networks to the transport of voice and fax over packet-data networks is providing a major market for programmable DSPs and the associated software infrastructur
W-CDMA enables 3G cellular design News & Analysis 4/27/1999 Post a comment Wideband code-division multiple-access (W-CDMA) is emerging as one of the main technologies for the implementation of third-generation (3G) cellular systems. The complexity of W-CDMA systems can be viewed from different angles: the complexity of each single algorithm, the complexity of the overall system and the sheer computational complexity of a receiver.
Oversampled data simplifies design News & Analysis 4/27/1999 Post a comment Multirate signal processing is an enabling technology that brings DSP techniques to applications that require lower cost and higher sample rates. While many of the techniques have been known for more than 25 year, others have a much shorter lineage. Recent activity such as the introduction of signal-processing chip sets and design tools directed to multirate applications reflects a growing awareness of the technology. However, using multirate solutions requires a slight shift in the system desig
DSP schemes navigate multimedia reality News & Analysis 4/27/1999 Post a comment Digital audio processing is the key to "full employment" for engineers. That's according to Tomlinson Holman, the inventor of Lucasfilm Ltd.'s THX theater sound and the keynote speaker at DSP World Spring Conference this week (April 26-28) at the Santa Clara Convention Center, Santa Clara, Calif. Holman argues that Dolby digital-5.1 speaker surround sound-is really not powerful enough to convey the realism of a dramatic situation on film or in a concert hall. The 5.1 topology, with left front, c