Santa Clara, Calif. - Smaller and thinner packages are making a leap into the standard-logic chip market as suppliers strive to support space-constrained devices. Ball grid arrays, no-lead quad flat packs and depopulated QFNs, and SOT553/563 packages are being pressed into service, as are such new technologies as Fairchild Semiconductor Corp.'s MicroPak and Texas Instruments Inc.'s NanoStar.
Integrated Device Technology Inc. and On Semiconductor offer QFNs, which tout both space savings and a performance improvement over such alternatives as small-scale small-outline packages and thin-scale small-outline packages.
Kevin Walsh, director of strategic marketing for IDT (Santa Clara), said standard packaging is giving way to smaller versions including the BGA and QFN in newer logic families. With no leads, such packages offer much lower inductance than in SSOPs or TSSOPs, which Walsh said yields better signal characteristics and faster throughput.
Earlier this year IDT introduced a level shifter that supports a 0.8- to 2.7-V operating voltage. The advanced ultralow-voltage CMOS device also touts 50 percent less propagation delay compared with other level-shifting alternatives. The AUC164245 is available in TSSOPs, TV-SOPs and BGAs.
Some logic vendors have also introduced depopulated QFNs. The DQFN is similar to the SOIC but allows customers to better route inputs and outputs, said Dan Huettl, director for standard-logic products at ON Semiconductor. The Phoenix company recently released more than 35 of its standard-logic, small-signal and diode array devices in small, no-lead (Pb), leaded SOT553 and SOT563 packages. The company said the parts cut board space by up to 70 percent.
The SOT553 package measures 1.6 x 1.6 x 0.6 mm for use in digital cameras, cell phones, PDAs and other small, wireless handhelds, Huettl said.
ON Semiconductor said the SOT5xx packages reduce footprint by two-thirds compared with the SOT23 and by half compared with the SC70. They also lower the board profile by almost 40 percent over an SC70/SC88 package.
Fairchild Semiconductor Corp. (South Portland, Maine) and Texas Instruments Inc. (Dallas) also offer tiny packages. Fairchild's new MicroPak for one-gate logic is claimed to be 65 percent smaller than the standard SC70, and TI's NanoStar is said to be 70 percent smaller.
Fairchild's TinyLogic eight-terminal MicroPak 8 is also said to offer a 60 percent savings over US8 leaded packages while maintaining a 0.5-mm terminal pitch. The 0.2 x 0.3-mm LGA contact pads ensure joint integrity. The package is available in the UHS high-performance, low-voltage logic family. Fairchild plans to offer the MicroPak 8 for high-performance 1-, 2- and 3-bit ultralow-power (ULP) and ULP-A logic functions at 0.9- to 3.3-V operation.
Fairchild has also made four additions to its NC7 series of TinyLogic ultralow-power logic devices for portable applications. They come in a choice of packages, including the six-lead SC70 and chip-scale MicroPak.
The combination of low battery voltage, low power consumption and chip-scale packaging offers optimal price/performance for portable electronics, said Ken Murphy, product-marketing launch manager for Fairchild's logic group.
TI's NanoStar saves board space when designing in logic, said David Hoover, worldwide product-marketing manager for the company's Standard Linear and Logic Group. "We thought it would only be valued in the portable space, but we're starting to see some migration into computing and other sectors," he said.