Analog Integrations

<p>Although analysts believe OEMs will continue to hold the upper hand in connector price negotiations, they face a bigger problem as weak market conditions and changing technology give suppliers additional incentive to eliminate slow-selling or unprofitable product lines or at least raise prices on these parts to cover losses.</p>

The challenge is demand, not inventory, John Gilbertson, chief executive of AVX, Myrtle Beach, S.C., said in a conference call with analysts late last month.

Power-managing ICs in wireless products are now playing a major role in system-level solutions. Cell phones, which are being combined with PDAs and cameras, are becoming increasingly small, dense and power-hungry, offsetting the size and energy density advances made by the lithium-ion battery sources powering them.

IC makers under the gun to redress the net loss in overall power margins are focusing on reducing the quiescent operating current of chips in the system to as little as one-tenth that of the previous generation. They're also adding more connectivity to allow wireless systems to sample the power environment and dynamically adjust to changing conditions.


Voice communication devices have become multimedia devices,” said Laurent Jenck, director of the Portable Power Unit at ON Semiconductor (Phoenix), noting the replacement market exceeded 50 percent of total units for the first time last year. That suggests that there's a more sophisticated audience of second- and third-generation users looking for more features, and thus a greater need to watch every microwatt. There's huge pressure to lower quiescent current. And there's a proliferation of different voltages and the need for dynamic programmability.”

With design targets changing very quickly, developers are taking a subsystems, or non-ASIC, approach toward power management. Such an approach establishes monitoring at the local level, yet keeps the blocks in close contact globally to maintain a watch on battery drain. The architecture is supported by a collection of chips, largely dc/dc regulator devices often running in the 1-MHz region. These devices have suitable control/supervisory circuitry that provides more efficient charging and have the flexibility to work from multiple sources like the universal serial bus.

Fuel-gauging devices keep more accurate tabs on a battery's remaining run-time. More wireless devices carry two displays, and usually both are in color, pointing out the desirability of more efficient white-LED drivers for double-duty backlighting tasks.


Standalone ICs have also arrived to perform photoflash charging for higher-resolution cameras that use high-intensity sources, which deliver performance well beyond that of traditional LEDs. Apart from the multitude of general-purpose, multivoltage baseband dc/dc converters for the current crop of wireless devices, specialized and dedicated dc/dc converters are coming into their own to distribute power efficiently to subsystems ranging from cameras to RF power amplifiers.

With the overall on-time of wireless devices tending to increase and the need for frequent and easily accessible battery charging becoming the rule rather than the exception, vendors have come up with a spate of new chargers that strike the best balance for a given application. The offerings include generally noisy but efficient switching-type chargers; pulse-type chargers, which may be more efficient but tend to complicate accurate fuel gauging and degrade the life of a cell; and low-cost but inefficient linear chargers.


The Linear Technology Corp. (Milpitas, Calif.) LTC4054 is an 800-milliamp charger IC for lithium-ion cells. It's suitable for charging batteries from a USB port.

Texas Instruments Inc. (Dallas) says its bqTinyII series represents the first 3 x 3-mm charger IC for single-cell lithium-ion cells. Features include the ability to charge a cell from a USB port or ac wall adapter. The series includes an internal FET rated at 1 amp.

To derive timing, the tool uses a fast physical-synthesis technique to turn users' RTL into a timing model to derive timing that is typically accurate to within 20 percent of the timing results of PrimeTime, InTime said.

The tool doesn't synthesize down to gates but [to] higher modules,” said Janac. Time Director does the same latch flop designware inferencing that is performed by physical-synthesis tools, but it doesn't have to go down to the gate level to derive timing. At that level, it is capable of doing placement too, so it generates accurate parasitics and an accurate area estimate.” Area is typically within 20 percent of physical-synthesis tool estimates, Janac said.

Time Director is a standalone product and can be used with standard third-party tool suites. It was developed for easy integration with existing synthesis and silicon-virtual-prototyping flows from Cadence Design, Synopsys and Magma Design, the company said. It features interfaces for industry-standard outputs.

An annual time-based license for Time Director is priced at $50,000.

Veo selected Ittiam based on their core competency in image compression technologies and in their ability to extend Veo's reach into a number of untapped applications that can benefit from lower bandwidth video de-livery,” said Jeff Stoen, director of product marketing at Veo (San Jose, Calif.).

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